Full caps are in my experience more secure and troublefree than toppers once you get the hang of wearing and applying them. They sort of mould themselves around your head.

I leave a narrow strip of my own hair at the back and this adds to the realism of the back view. I mostly use the Full cap sideburns and just shave my own off underneath.

Generally I tend to use mostly tape now which is quick and clean. Glue is sometimes useful across the very edge of the hairline and tip of the sideburns, but for most day to day situations tape suffices. I find Walkers No Shine good, and so too Duo tac.

To get rid of the slight shine that still seems to exist with lower densities at the hairline (even with Walkers though it's not a s bad as most other tapes) I unpeel the tape before applying it and spray it with Mane (sort of like Dermatac in a spray can). Not a hint of a shine after that and it doesn't seem to adversely affect the strenght of the hold.