Hardware :: Transitioning From 802.11g To 802.11n

Currently I have two 802.11g Airport Express adapters. My setup is that I have my cable modem feeding into AE #1 (which also plugs into a stereo next to it) and then AE #2 is working as a wireless bridge in another room (and plugs into a stereo there). My apartment isn't nearly big enough to warrant both adapters, but I like having the ability to stream to either stereo. On my network are a variety of machines, some of which are 802.11n capable. Presumably the proportion of n machines will increase over time. What I'd like to do is to get an 'n' device as the base node of the network. This could be one new airport express to replace AE #1, or perhaps it could be an airport extreme (I do like how it has actual ethernet jacks). My fear is that using the 'g' adapter(s) on the 'n' network will cause problems. For instance, my desktop sits next to AE #2 - if that one stays here and the base network is upgraded to 'n', will my desktop simply connect to AE #2 at 'g' speeds? I suppose one solution is to simply replace both AEs with new AEs for the cost of a single airport express.