Very nice reviews and pictures, thanks indeed.
I am about to purchase a GS Solo, and still hesitate between the SRG II and U/L... I have read that the U/L can be noisy with high sensitivity cans, which would be my case (110dB/mw for the DT48A). Anyone can confirm this ?
The GS Solo is one of the very few "affordable" amp around that I know of and has a high impedance output at 120 ohms. I guess this explain why it does offer good control even for demanding headphones like HD800.