I bought our mower 9 months ago. I did my homework and read the customer reviews which appeared 50/50 in their opinions (like/dislike), the main complaint seemed to be the battery/charger. My dad always used Bosch power tools as they were a good, quality brand so I went ahead and bought one. The mower worked great - cut the grass as good as any petrol mower, was quiet and lightweight.Then I noticed the battery would go flat faster and faster until it didn't charge at all. I've since had it repaired under warranty (Bosch replaced the battery and charger). It's charging better than ever before so I suspect the battery or charger was faulty from day one. Overall a good product if your charger works.

We bought our Bosch Rotak 37 Li cordless about 3 years ago from Bunnings for $600 I think and we love it.
It is just so convenient, quiet, and gets the job done. We don't have a large lawn but it takes us about 25 minutes to cut and we get it done on one charge. The charger gave up about 4 months ago but found one from some Sydney tool Company for about $180.

Update 30/4/16
Our latest charger, number three, has now died and we are trying to negotiate with Bosch to see if they will supply another one. We reckon 3 chargers (recommended retail $249) in 4 years is a bit much. Otherwise we still love the mower which does a fantastic job.
Easy to use, light, quiet, no petrol, oil, plugs to worry about
a bit expensive but worth every cent

I loved this mower, worked well for almost three years. Then the battery didn't charge. Wasn't sure if it was the charger or the battery so I thought I would look at both. Bunnings no longer stocked this mower, so it took a while to get the prices. For both the charger and the battery... $520.
So light and easy to use.
Apparently it is disposable.

I bort my Rotak 37 in 2010 and its still going. Of late its been hesitant to start so Im worried its on its last legs. Symptom - motor whirs for 1 second then stops. Try it a bit later and it starts. Battery seems fine, showing 3 bars. Hopefully it will last this spring and summer. Im on a 540sqm block with a decent lawn at rear and modest front.

In terms of the last 3 yrs usage - no complaints. Its perfectly fine for modest lawns and modest tasks in suburbia.
No petrol hassles! Light. Seems well-built.
In its 4th year of operation it occasionally doesnt start, but still hasnt died. Fingers crossed!

In my opinion, a cordless lawnmower does not seem to be a great product. Mainly because the battery has lifespan, nobody can assure after 2 years usage a fully charged battery is still a long lasting battery.
I personally prefer a corded lawnmower, although the cable might short, but it can always buy an extension cable.
Convenience, light, great design
Battery lifespan

I started off loving this lawnmower. No petrol, quiet, lightweight and with 2 batteries I could easily mow my entire lawn (about 450m2). Then after only 3 months - it stopped working. Completely stuffed. After a $300 repair (I had bought overseas so Australian consumer protection didn't apply) it was up and running again...but not for long. It's now died for a second time. Same problem. Disappointing. I'm not going to waste money trying to fix it again. Going back to petrol until the technology improves!
No petrol, quiet, lightweight
Has broken down twice in 18months. DO NOT WASTE YOUR MONEY

I had a BR 34LI for just about 15mths. I like that its light and fast to move. It wasn't so great when I let the grass get long, or if it was wet. At the 11 month mark, it started to cut out. I took it back to Bunnings and waited 2 weeks to be told nothing was wrong. It was fine for another 1 month and then again started to cut out, and refuse to restart for long periods. I thought it was overheating but discovered that it would restart only when I applied downwards pressure on the battery. Eventually, even that stopped working.
Light and easy to use.
Service department wasn't very thorough in my opinion

After fighting petrol mowers for over 40 years and watching the grass grow ever longer, I bought this Bosch lawnmower.

I mow every week now, my garden and lawn have never looked better thanks to the rain and my Bosch.

Take it from me, don't fight your old petrol machine any longer.

Get this mower, you won't regret it.
Ease of use. Reliability. Light weight for lifting.

Every Lawn mower in future will follow this design leader.

Brilliant design, world class product. Lightweight, Efficient.

I purchased the Bosch Rotak ergoflex 43Li from Amazon UK, delivered to Australia. Came with 2 batteries.

Perfect constant speed. Stops immediately if grass catcher full or encounters an obstruction. Excellent electronic stall protection

I believe it uses regenerative techonoogy to recover the rotational energy of the blades at the instant it is switched off.
Perfect

Read enough reviews before deciding to buy it. Mainly for it's light weight as I have a few patches of lawn that require the mower to be carried across.

Bought the 43 LI from Amazon Germany as they can organize shipping to Australia. All up around A$550 including shipping.

Used it a few times now and happy with the mobility and the cut, even on wet long grass.
Light weight, easy to handle and carry
Not sure how the warranty will work with import to Australia

All the reviews below echo my positive experience as a grandmother who has never mowed a lawn in her life until now. I did the research and decided the expense was worth it- no cords to worry about and quick charge to get the job in an hour- large house block. The new Masters store has it for just under $600 - cheaper than what I paid a few months ago.

This machine has clear advantages in noise, pollution, ease of operation and the quality of the mowing outcome. Low operating and maintenance costs can also be added to the list of advantages.

Because of its light weight and low noise this mower is actually fun to use and its environmental advantages provide a feeling that is hard to put a dollar value on.
Manuverability, No fumes, Low noise, low maintenance costs, light weight, green credentials.
Initial cost

Female-never mowed a lawn in my life, plus have had 2 ops on arms in past 12 months. Bought this as so over being charged exorbitant rates to get my lawn mowed. Extremely light and pleasure to use.
Easy to put together(except the grasscatcher), and battery charged up quickly. Started straight away, no problems at all using.Lawn looks great!
Can't work out why its $300 AU to buy in UK and double here. Not right in this day and age.

A great mower but the one I chose (37) is too small for my 1/4 acre block, however it will do. With only one battery, beer time comes around quickly.
Light & the wife can use it! (weight is 60% of equivalent petrol mower)Quiet, can cut the grass at Sunday lunch time
Catcher is too small.Bosch should ship it with a second battery to increase cutting time.Cannot handle gum nuts - they jam the blades & can be hard to remove.