I've owned and played lots of this stuff. And here is the one and only reason I find the graphic Eq effective .....because the midrange control pot does almost nothing on the Mark amps. MArk 2 and 3 heads are midrangey and all I ever do with the graphic is cut a little mids on the 750hz slider.
For recording purposes , I have more than enough expensive EQ plug ins to do the job for me but for live playing, I can see the graphic EQ as being needed to control the abundance of midrange.
If you do get one without an EQ (not a problem in my opinion ) and choose to put something in a loop , consider using a quality parametric like a Rane PE-17 or a TC Electronics . Boss EQ pedals are toys with the sculpting power of a butter knife.