[JRTJH]

If I had to have a patch on a EPDM or TPO roof, I'd prefer it be on the actual RV roof, not on a slide roof. The "wipers" and "seals" on a slide tend to drag over the roofing, adding a potential for the patch to be "peeled away" as the slide is retracted and extended for use. If there's any part of the roofing system that, IMHO, should be intact without repairs, it's the slide roof. YMMV