We've (read: I've) been really happy with the KitchenAid gas cooktop we put in when we remodeled the kitchen 8 years ago. It's not high-end, I suppose you'd call it a mid-range model. 4 burner, electronic ignition (don't think you can get anything else any more). The base surface is glass and cleans up easily. I don't think I'd like one with a stainless base surface, but that's only opinion. 

All our kitchen appliances are KitchenAid, and have been great for 8 years anyway. Love the french-door fridge and dishwasher. Our double oven got damaged by lightening and was replaced, so it's only a few months old. It's the updated version of the original model we bought back then, and the standard upgrades are really nice.

Have fun shopping......you'll have a lot of questions and learn a lot.