Had one for about 3 years. I had Dyn C1 sig and Raidho D1 and D2's for speakers. I think I'm the oddball that never cared for the KT120 sound. Very forward and didn't sound balanced from top to bottom. One nice feature of the V110 is a switch on the back to allow for lower power output tubes like the EL34/6550/KT88 (changes plate and grid voltages). KT150's will work just fine but you won't get and more power compared to the KT120. I did swap many different tubes and all I can say is the speaker will determine which tube sounds the best. ie TS original 6550 black plate sounded the best with the Dyn's. Ei KT90 sounded the best with Raidho's IMO. YMMV
I also had the black box which significantly lowered the noise floor and gives you a hair more headroom.