I have a Baumatic which has served me very well. Here are my tips ...
Make sure you get the big heavy cast iron grids or pan stands or whatever they are called (the bit that goes on top of the gas ring to rest the pans on) as some of them (like the enamelled, thinner variety) can be a bit tippy when it comes to pans. I like that I can slide big heavy pans over mine without them wobbling or tipping up.
Yes to stainless steel.
One thing I hate about my cooker, and it maybe a ridiculous safety before comfort measure which is unavoidable, is that the normal sized rings you use the most are at the back. I have a big wok ring in the middle - fine - but then a big, burny ring on the front left and a ridiculously small single-person-heating-up-one-portion-of-frozen-peas style ring on the front right. This has annoyed almost every day since I got the cooker about five years ago.
My oven is shite. I'm not sure why. It is electric and supposedly fan assisted, but it cooks too hot, burns stuff, uneven and just generally bollocks. I'm a good cake maker but this oven is failing me badly.
When you have your range cooker installed, make sure they put it in evenly. Most have adjustable legs. Mine is uneven so oil falls to the front slightly in the frying pan, cakes in the oven tilt etc.
God writeen down like this I can't understand why I am putting up with this cooker. I'm in the process of getting a Rayburn which will also heat my water and radiators.