My deck has 10,000 hand-made cards and I know for sure they stick in my brain easier than cards from a premade deck that I have no connection with. I suspect it depends how you make the deck. I intentionally use sentences and images that I care about.
It only matters for the first few reviews though, even a premade card can be forced into my mind with enough effort.
probably depends on the type of material too. if it's purely memorization (e.g., I'm learning spanish as an english speaker) then there's probably no difference. If it involves any sort of understanding then I'd be very surprised if there was no difference, at least in speed of learning
It only matters for the first few reviews though, even a premade card can be forced into my mind with enough effort.