I used one of these services for a laptop when my freelance work dried up temporarily. The biggest hurdle was actually finding the manual payoff option in their app, it was buried three menus deep. I got paranoid about the deadline and started searching for the
snapfinance phone number so I could talk to a human and confirm my zero balance. The automated system is okay, but getting a live person to email you a "paid in full" confirmation letter is the only way I felt truly secure that they wouldn't hit me with a surprise charge later.