No, I don’t think I noticed any difference (but I don’t have that many sales yet to see any pattern). Actually, one customer bought two works at the same time, one through PayPal link on DPW and then clicked and paid on Etsy for the other one. So I guess, it’s not such a big factor - if they want the work, I don’t think it makes much difference how they are offered to pay for it (of course, some people had problems with PayPal and want to avoid it).
By the way, I have both PayPal and Etsy “buy” links here because I’m too lazy to list everything on Etsy right away 
It does take more work to list there - to come up with tags, title, description, so on. So some auctions that expire here are just switching to PayPal links because it does not take any extra work on my part, not because there’s any real strategy behind it.