Get the cheapest AP you can get, if you don't want to have some extra-options like 256 bit WEP and so on. I tested many APs for writing my book and all are good enough to work with the empeg. If you want to use more than one AP to connect to clients, think about the throughput. More than 3 APs will drop the throuput down and you should try channel 1,6,13 not 1,2,3. Give them space. If you want to connect an AP to an AP, which seems logically for the empeg an the homestatione, there are only a few APs who can act as a client, so be careful.
I set up a site dedicated to the wireless empeg-connection. Not much at the moment but might be growing. http://empeg.rowi.net.

regards,
Rolf