I personally prefer using only one Trading strategy, During my early trading days i went through so much strategies from one to another to choose the one that best suit my style. After a while i was able to pick one don't think i will ever use another strategy apart from mine to avoid complications.
In my own case, I'd prefer making use of a single strategy but when am using that for a long time and over this period without having a result to back it up then i try to switch or change to another maybe i could use another approach to get a better experience with my trading, this is how I've been always staying with these kind of situation because i like holding onto something but not when am not having good results from it, then i try to refrain myself for another option.