Wherever possible I prefer to engage when a swing is in progress jcp, the method behind that madness being I usually get to stick the stop behind a reasonably formed pullback level that is honouring a shift up/down in momentum, particularly if it's an intraday bet (which I must admit is rare lately).
If I need to locate such a level that necessitates a larger than normal stop I simply reduce my bet size to maintain the desired pecentage of equity allocation.
Obviously, every situation warrants a slightly different decision. It needs to be a flexible arrangement based on the objective for that specific trade, the pair in question (as some are more volatile than others) & the circumstances surrounding the entry.