I use stainless extensively on my bikes and have done for some time now. Its excellent stuff and has a lot of advantages but as Trevor has pointed out it also has some drawbacks, the main one being "galling" or picking up, this is when the nut "welds" itself to the bolt.
There are a couple of things you can do when using stainless and the main one once again as Trevor has pointed out is to use a anti-sieze compound. When using stainless you must use one of these compounds, not should, must.
Another thing you can do if you have a situation where you may have a internal thread on something and you are going to screw a shaft into that is to use different grades of stainless, for instance make the collar out of 304 and the shaft out of 316.
I use mainly 316 as it is a lot higher tensile than other grades, nearly impossible to strip the thread on a 316 bolt. It doesnt rust and when polished looks almost like chrome, its a excellent replacement where nickel plating was used. It is also available in hex bar in witworth sizes so your 1/4''/5/16"/3/8" etc spanners fit correctly. The drawbacks are its very hard on your machine tooling. I make most of my stuff on a lathe and use tip type tools but if you use taps and dies then it will blunt them very quickly. It can also be hard to indentify what grade you have, the industry uses a colour coding to identify the grades but unfortunately different companies use different colours so you can never be 100% sure what grade you have until you start machining it.