Thanks for the insight. AppleTV would seem to be the better solution (better optical connector, PS,..etc), although it has a cord. The AE is more compact, no cord (plug directly into power conditioner), but has mini-optical output, probably poorer PS,..etc. and as some have pointed out doesn't sound as good as AppleTV. I'm sure plugged into the power conditioner, and even having it modded with better PS, connectors would only improve it.
My iMac and AEBS and AE all support 802.11n. No worries there. And with regards to the SBT rebuffering issues; I've tried every setting/combo with Radio Modes, Multicast Rates, Interference Robustness,..). However, I don't see adjustment settings (buffer/steaming) for Squeezebox Server or SBT. And if it's a known issue, then it's been known/ongoing since SB3.
I have an AE I could try but no optical cable. Annoyed that I bought a D-60 for the SBT. The $99 to try AppleTV is not much (can always return it). Plus I can pick up an decent optical cord for not much more. I came across mention of the van den Hul Optocoupler mkII being quite good.
But at this point I've given up on the SBT. It's not just the rebuffering issues, but I'm also disappointed with the GUI. I expected something more like iPod Touch. A rather rudimentary designed UI. Not very intuitive either with navigation.
I've also decided to give USB converters another try with the Halide Bridge. This gets a lot of priase and I'm very curious as my experience with these devices 3-4 years ago was terrible, even USB DAC's from $1K to $3500 didn't satisfy me (compared to what I was accustom to hearing from my previous Accustic Arts CDP. Up until recently I used the iTransport/iPod -> Reimyo DAP-777 and was beyond satisfied. I've always wanted to use my iMac/iTunes/Front Row as a music server though with the Reimyo, but without having to spend a lot more on over priced digital interfaces and w/o having more devices and cables and wires. I want to keep it simple. Hopefully I can find some peace with either AppleTV or the Halide Bridge.