From a quick look at some reviews on the IPS-1 and the measured power output, (188 watts x2 channels into 4-ohms at 0.1% THD), I think you'd have to either have a big room or listen at insanely loud levels (or listen at moderately loud levels to classical music with a large dynamic range) to really notice the additional power available from the A1400.

For a lot less money and more noticeable impact, I'd put up QS8s as well and save the rest of your cash.

Jason

Epic 80-800: HG Cherry