I had a PSB skin system that I used for this purpose, I could slap it on with G2BG in a matter of a minute or two. It would hold fine for one day, I just used a comb down style and didn't worry about the hairline. I also used clips for a short time when I first started wearing. IMO, using clips with a topper system is more prone to causing traction alopecia or irritation in general. Because the clips are somewhere near the middle or top of your head, and the topper has to stretch a bit between them. The only reason I used them was to attach without shaving underneath.

I just got one of the new very thin skin systems, unfortunately G2BG doesn't hold well at all with it for me. I will probably get another "old style" skin system for this purpose, I really like having the security of knowing I can throw it on and be ready to go in a minute or two - that is, if I'm lounging around bald and something comes up, an unexpected visitor or whatever. I do like leaving the system off for a day or two, just wear a ball cap.

I don't know about using synthetic hair, I've never tried it but I don't care for the look of wigs that I've seen in person that are synthetic. I think it depends on how it matches your own hair texture and color, one guy here was using it and posted pics that looked very good. Remember also that synthetic knots can't be bleached.