"Now I use the X250.5, overwhole sound I prefer a lot more over the XA60.5."
This is a very system (and listening preferences) dependent statement. For example, I auditioned the XA30.5 vs. the X250.5 on Thiel 2.4s. The X250.5 had some midrange harshness that made it slightly grating on the Thiel's and made the vocals (even Kanye West's) less natural. The XA30.5 has much more natural sweetness and a better soundstage (with those great vocals), but is somewhat weak in the bass. I think this is an issue with the XA series in general, which makes people think they don't have enough power, and draws them up the line (hence the XA60.5s becoming available). I personally love the XA amp so much (even though it's underpowered for my speakers) that I just dealt with the bass issue by adding a Thiel sub. I also know someone else who was looking into speakers with powered bass units for the same reason. In any case, the Pass amps are awesome, and the impression I've formed is that if you want great bass, you should go with the X.5 series, but if you want great soundstaging and vocals, you should go with the XA series. Also, just fyi, both of these amps just killed a McIntosh MC-402 which another Thiel 2.4 owner had loved.
This is a very system (and listening preferences) dependent statement. For example, I auditioned the XA30.5 vs. the X250.5 on Thiel 2.4s. The X250.5 had some midrange harshness that made it slightly grating on the Thiel's and made the vocals (even Kanye West's) less natural. The XA30.5 has much more natural sweetness and a better soundstage (with those great vocals), but is somewhat weak in the bass. I think this is an issue with the XA series in general, which makes people think they don't have enough power, and draws them up the line (hence the XA60.5s becoming available). I personally love the XA amp so much (even though it's underpowered for my speakers) that I just dealt with the bass issue by adding a Thiel sub. I also know someone else who was looking into speakers with powered bass units for the same reason. In any case, the Pass amps are awesome, and the impression I've formed is that if you want great bass, you should go with the X.5 series, but if you want great soundstaging and vocals, you should go with the XA series. Also, just fyi, both of these amps just killed a McIntosh MC-402 which another Thiel 2.4 owner had loved.