Yeah I don't think we really have any noticeable 'hoppers' as such.
Though, it only deters them by the design of the payout for everyone - the delay in rewards - it has no affect on their total rewards, they expect to get the same total rewards as everyone else, based on their hashes submitted to the pool.

But certain failover's have had historically good luck.
While historical luck doesn't mean anything about the future, it does directly mean they've been advantageous to the pool so far.