Class A 30 Watt Amps: Are they enough to drive my book shelfs?

I have a Pass Aleph 30 powering a pair of Kef Q100’s. More than enough power for me. I also use a powered sub to fill out the low end. 

I believe John Atkinson (Stereophile) measured the Pass Labs 25 watt amp at 80+ watts in to 8 ohms, and 130 watts in to 4 ohms.. The amp in question should have no problem with the KEFs.

For those folks with experience listening to 30watt class A amps, how would the Pass Labs XA 30.5 compare sonically to the pass labs 150.5 A/B amp?  Other than more power & better bass control (with the 150.5) is there a unique listening experience (with pure class A) worth chasing?

BTW- thanks for the previous thoughtful responses on this.  

Since it looks like nobody asked this question, why would you want to invest in a class A amp to drive KEF bookshelf speakers? Dynaudio or the equivalent maybe, but KEF? Better off to invest in better speakers and live with a class AB amp; much better bang for your buck.