I use Swapface a lot , I think I can answer you. The app works very well, expecially with pov videos. Basically, If you have a good angle of the face the swap will be great. But if you cant see all the face, in blowjobs and in kissings, the results will be bad. You can use the hybrid mode for bj, sometimes it gives you aceptable results. For example, NetvideoGirl castings videos works very well.
The app give you a 20 swaps for day(10 photos and 10 videos) for free, but if you registered with a friend code, they will give you 30(15, 15). I can give you my friend code in pm if you want.
This are captures of two videos, Andrea Botez and Waterlynn. If you dont want the logo you have to pay