Soundwise you can dial in the fx8 ODs into almost od pedal. Their tube screamer is really good and listening in the studio not sure how much of a difference is there. Not much if any, and the easy of internal switching make it a great board.
However...I decided to take my mxr od to practice last night. There seemed to be a huge feel difference at loud rehearsal volume. I usually tap dance on the fx8 anyway, so I'll keep the xr od on the board. It sounded awesome either way but the pedal gets the nod for me today.
I also threw an ISP in the loop. The noise gate in the fx8 is in the pre section. When I play hi gain tight riffage it works great, but then going for dynamics on a dirty tone the gate can get in the way too much. You can program each preset but I like those knobs handy so ISP is on the board now. lite fx8 gating in the pre and aggressive ISP setting in the loop that I can easily stomp off.
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