I have had a couple, and have my mums now and I bought one for MIL last xmas
They are all basically the same, but features I found better were the fold down paddle (the ones that don't are mighty annoying as you have to dig it out of the loaf!), different size loaves, timer (so can set to cook over night and be ready in morning mmmmmmm), dough maker - really good for doing buns etc, and also one that beeps when its time to put the seeds in bread
Other than most of them have standard stuff like different bread types, colour
One thing I wouldn't say you need (even though it sounds good) is the speed loaf - they are horrible...much better to do full setting!
when you make your bread I would ignore the salt and sugar it states - if it comes with a spoon thing use a big end of sugar and a small end of salt - they say some hideous amount and the bread tastes awful!