krell ksa100 vs. audio research 150.2

Depending on preamp, my choice would be the KSA100. Its one of Krell's best ever. On the other hand, with satilite as a source both are overkill.

Well, there's hundreds to choose from. Would need to know what preamp you intend to use, what kind of upgrade path you are looking for, your budget, and your system goals (ie: is there something in particular that you want to improve upon?).

IMO the sound quality of satelite radio is marginal at best. Therefore, the best amp in the world won't fix it. When you heard the AR at your local shop, was the source satelite radio?

Either of the two amps you mentioned above will make your Vandys sing if the source is good. Easiliy achieved with a good CD player or turntable & cartridge.