The TSL122 came stock w/ a Wolverine speaker. You could upgrade it to V30...I prefer my TSL100 with V30 if I use one cab. I use 75T on It if I play with full stack.
The Wolverine was a bland speaker. Kind of like a hi-fi midrange speaker. That was supposedly the speaker the TSL was "voiced" for...
The TSL has a peculiar midrange frequency. It tends to work better by way of subtraction, than boost, but, you don't want to scoop it too much. It has a fine line. Once dialed in, it sounds great, but, you can't just crank up the mid's like you would on most other Marshall amp's...
That said, the midrange doesn't play well w/ all speakers. The 75 are a safe bet for almost any amp. They are pretty evenly toned & are mellow, w/ decent breakup.
The DSL, is more traditional in it's tone (midrange) & goes w/ just about anything...