Wilson Audio Sasha 2 vs Sophia 3

How can you really tell how much current an amp has.  All that is published is the watts, typically.  I know "not all watts are the same" - which I've always interpreted as some have more current/guts than others...  Can anyone point me to a layman explanation AND a way to tell how much current a given amp has?  Thanks!

"Typically" an amp that is solid state with big power supply and using bi-polar output transistors (BJT) are the ones that will give the best current output.
To put that into laymans terms, an amp that can "almost" double it’s wattage for each halving of speaker impedance load is a good current deliverer.
Look at the specs.
EG:
50w -8ohms
100w-4ohms
200w-2ohms

For instance very sought after huge old massive Mark Levinson ML2 monoblocks don’t have many watts into 8ohms but they do
25w-8ohms
50w-4ohms
100w-2ohms
200w-1ohm.
https://c05d22d421713559ae3382d5a980815d4cf5ca6a.googledrive.com/host/0B_s-XMmdi448RDhFR2hhdXVQRWM/Mark-Levinson-ML-2-Mono-Power-Amplifiers-.html

Tubes and mosfet amps, don't do these sort of currents, that why they don't usually advertise it. 
Cheers George

Thanks again, George. 

I do know that my ARC does not increase/decrease W according to impedance/ohms.  

I should have my Sasha's here in the next week or so.  It will be quite the comparison; going from very efficient and quite easy Focal 1027S to the Sashas.  I don't think the Focals have pushed my amp much, but I expect the Sashas to lay it out.  
I know the Sashas can do much more - in the bass for example - than my Focals.  Something like ~15 Hz lower or more before -3db, for example.  I'm not sure if the little VSi60 (KT120s) can power up the Sashas enough to be a significant improvement over the Focals, Or if I'll need much more amp to hear real gains.  
My guess is: The Sasha's will sound much better than the Focals, immediately, all around, but they will still be far from giving me their all with the VSi60.  

Next step is a step up in the ARC line via separates.  

Thanks again!

Wow! Where were you guys on my best headphone thread?? Wilson, Levinson! True dyed in the wool audiophiles! While I'm here, looking for Levinson 535h amp! Used if possible! Thanks!

It's been awhile, but figured I'd do a brief update in case anyone stumbled upon this. 
System is now:
Sashas
Ref 3 pre
Ref 75 amp
Lumina T1
Transparent ultra cables

@georgehifi I've really enjoyed the system with the 75 for a year.  I did drop in a SimAudio Moon 860A just to see what the Sashas can do with more power.  It exposed, as you produced, much more to the recordings.  But, over all I'm a tube guy, and prefer my 75 over the bigger Moon.  Having said that, I'm considering moving up to the ARC 150 now to get a bit more base grip on the edges without (hopefully) giving up all the rest - which is perfect for me.