Pass labs Upgrading from X350.5 to X600.5

I wish to know from (users or others who have auditioned) both the Pass Labs amps - X350.5 & X600.5

What are the major differences you would notice immediately when you move up from X350.5 to the X600.5 ?
Esp. in Soundstaging ? Does it get bigger and deeper ?

Will appreciate if you'll let me know.

Thanks for reading.....
The 3 major physical improvements are more power (obviously), having separate power supplies, and doubling the peak class A power (80 watts vs. 40 watts) before it switches to class AB.

I found the bottom end to be more extended and under better control. The presentation was more effortless and relaxed. The music would flow without any hint of strain on the loudest passages. It would probably depend upon your speakers.

I have found the source and speakers to be larger determinants for soundstaging compared with the amps.

Although many speakers do not require 600 watts into 8 ohms, having the extra headroom for class A would be welcome by almost all speakers. Although I had not directly compared, it is probably similar to having an XA80 with a much higher peak power.

The downside is cost ($3-4k upgrade), the need for another cord/outlet/stand, and double the heat.