We haven't had any problems with our 13 year old Highland cook-top HP6SSN, but ..... it's the only natural gas appliance we have, the bill is about $6 for gas and $50 "Daily charge. We looked into converting it to LPG /propane, but can't find the conversion kit!
Any suggestions?

Constant problems, clicking, failure to light, gas remains on when it should off and shorting in the igniter that has blown the entire kitchen circuit. But worse is the fact that there are simply no parts available. I have had the local service agent out four times now but he cannot get parts anywhere. Now I have to use a BBQ lighter. I managed to buy from EBay - for a hugely expensive cooktop this is just not good enough. Do not buy one.

I always had Ilve Cook tops and ovens but wanted the low setting for gas these have. works great except 1 or the 2 wok burners keeps ticking. had several service calls which came when they scheduled but telling me its the pots i use or the size of pans and other rubbish did not wash. just booked another service call today and they say the part has been redesigned and they will swap both wok burners parts out under warranty. not sure what parts but suspect the gas reader or the igniters.
Will update this post after they finish the service. I will also expect they restart the warranty on all the parts they have been servicing and replacing !

Purchased the Highland cooktop, it was the worst decision I made for my new kitchen. It was sold to me as being a premium product, but after 3 service calls later and having to wait for 3 months for parts and for me to do all the follow up, I would recommend buying another brand.

Within few months of installing the cooktop, the igniters on the wok burners became faulty - they would keep sparking even though flame was on. It took 3 visits from technician to fix it. Now my warranty has expired, the igniter on medium burner works intermittently. The black coating on the trivet where wok sits has started to come off. The knobs were always loose and wobbly when it was new and technician never bothered to fix it. For such an expensive cooktop, the quality doesn't match it. I wish I had stuck to ILVE cooktop which I was very happy with.