I always have both freted and fretless with me on my bi-weekly church gig. I use a Genzler Magellan Pre as it has two pre-shaped EQ curves which makes it nice and easy to dial in, one for the freted and the other for the fretless. A touch of Keeley compression and I'm very happy with my mwah. Thus said if I was only to gig the fretless I would go for a fishman platinum pro EQ as it does everything (EQ, DI, tuner & compression) in one box. The other bass player at church uses one of these and his tone is great (albeit on a five string with frets).
Mind you as a Trace Elliot fan I've always been tempted with the Transit B pedal that also does everything, but never actually tried one for myself...