+tone sucker to death
Hummy daw.
Even the original Sans Amp GT-2 is hummy. Years ago, I owned a Behringer GDI21 and GT-2, compared them side by side and they're virtually identical, even the "hum". There maybe a slight tone suck on the GDI, but it's negligible, unless your audience has bionic ears like most tone/boutique snobs here in the forums.
BTW, I sold my GT-2 (used the money for pickups instead hehe) and used my GDI21 on countless gigs w/ no complaints, didn't really feel a difference.
If you want more than a GT-2, then follow Bolt Thrower's advice and use a DistStation.
If you're a bargain hunter a.k.a "kuripot" (like me, hehe) w/c believes tone is in the fingers and has a strong make-do/DIY attitude, then go fo the GDI21.