At the risk of seeming like a wise guy (not at all my intention), if you have only been climbing since last spring, any shoe you've worn has incredibly sticky rubber compared to what many on this forum climbed on for years (or decades). Your footwork will improve and I would guess that if your feet slipped while chimneying, insufficient counter pressure was more at fault than the stickiness or not of the rubber. That said, having my shoes resoled with C4 (when they are needing a resole) has helped make all of them stick better (with the disadvantage that they wear faster). I have worn La Sportiva shoes now for years (they fit me best!) and have been very happy with the original rubber--I've never worn Mythos, but friends of mine regularly climb harder in Mythos than I've ever climbed in anything. I guess my point is that the rubber is part of it but not the biggest part. Climb a lot, try different shoes, and have fun! You've already tried two of the many brands out there-- I agree with sneoh--Fit is Key!