Pass 150.5 vs. Pass 250.5 ?

Focal JMlabs speakers are very easy to drive, I'm driving a pair of Micro-Utopia's with about 20 tube watts. I think that the 250.5 may be overkill, the 150.5 would not only be sufficient but might sound better as well.

Jond, your speakers are monitors.
1027BE are floor standers. I don't see any relation between these 2 pairs of speakers. Your last statement is a bit confusing. Can you please expand on how the 150.5 may sound better than 250.5 on 1027BE?

Jond is right. At least partially. These Electra's can be driven even with 300B SE amp. I tried it at home with Audion 300B and I had quite good result with it. Very nice and open mid-range with quite good bass extension and excellent timing. The problem is that I am looking for much better and more authoritative bass control - one that I had with Bryston 4B-SST (which on the other hand was a bit closed in the mid-range). Therefore, I am formulating my question now a bit different: would I get these virtues with Pass Labs X-150.5 ?

Dejanm, excuse my ignorance, but I don't get it.
You say that the speakers are efficient enough to be driven by a 300B SET amp, yet you mention you liked the bass control of a SS amp that puts out hefty 300w/ch into 8ohms. You want a 150w/ch amp to have the same bass control?

Audphile1 I was making a general comment on the efficiency of JMlabs designs, and since floor standing speakers are typically more efficient than monitors it stands to reason that if my monitors are efficient than a floorstanding model from the same manufacturer may be even more efficient. My comment on the 150.5 versus the 250.5 simply takes into account the commonly held, and with good reason, belief that a lower powered amp from a given manufacturer will sound better, usually sweeter and more pure, than a higher powered one. Given that, plus the fact that I've read many users who state that the 150.5 is a better sounding amp, even to the point that a tech at Pass said it to someone as well.