when I ordered my unit, I trimmed the lace down and left only about 4mm excess at the hairline. When I attached, I could always see the lace, especially since I (up to date) never get all the hairline perfectly down (I use glue for the front).
So what I did, while it was still on my head, I pulled the hair back and trimmed it to hairline as much as possible. it looks so much better now.
I havent tried taping it though. when I did it (I had extra lace), the tape left a shine which I didnt like. I might give it a try now that its trimmed to the hairline. Good advice snipe.