I've never tried the 2:50, but I own the 50/50 and its a fabulous power amp!
The differences are:
- 2:50 is newer (mid 90's to present)
- 2:50 accepts both 6L6 and EL34's, where 50/50 only takes 6L6's
- They look different (duh)
- The 50/50 has a low power switch that knocks it down to 17 watts. 2:50 does not have any low power switch.
They probably go for about the same price on the used market.
