Having over 15yrs experience with a "tip&dip" system, and 3 with UV Gel, and after reading all that I have (meaning: learned all that I have from THIS site lol).....And after having reformed several biters...... My personaly opinion would be L&P or UV Gel would be better.
Biters are notoriously 'hard' on their hands, as they've never had nails. When you have nails, you use your hands differently. I don't need to explain that, I'm sure.
Even biters that are determined to reform and sincere in their efforts will experience a LOT of breakage/lift in the beginning BECAUSE
A) they must learn to use their hands differently
B) their fingers will still unconciously find their way into their mouths and pressure will be applied.
L&P & UV Gel (in my opinion) are stronger. I don't feel that it will cause 'more' damage to pick one type of system off, more than another. They're all made to stick, and will ALL leave damage if pried/picked/chewed off.
But even with the strongest system or methods.. I find it's more how you handle/deal/help a biter, than what system you use.
The approach I find that works best with my "biters" is this:
HONESTY
As a former biter myself, I KNOW what we do. I tell them this. I tell them how I know how hard it is to stop. I tell them how I was just as bad in the beginning, picking at them myself, etc... Using examples to show that I really do understand.
How sometimes the temptation is just too great to bite/pick/pry off the enhancements. I make it clear that I CAN and WILL know if this has been done and that they do not just 'fall off'. I even explain how I know, and why it leaves damage where "falling off" wouldn't (meaning: if they're stuck, they'll rip off layers. If they are "unsticking" on their own, then they won't rip off layers because they weren't stuck. Simple logic really.) I explain that I want to help them. That I know they can do this. That they may trip up now and then. That's ok. It happens. We'll fix whatever has been done and kick this devil together..
In the beginning, I treated biters the same as other clients. It didn't work. They really needed that extra chatting, and explaining. They needed to know that NO, I won't berate them for slipping. That I do understand.
Right now I have about 8 reformed biters. They are doing FANTASTIC. None are picking/biting/prying anymore. They are my best clients and my biggest fans, referring clients left and right.
So, back to the original question: while L&P or UV gel might be strongest (because they have to learn how to use their hands differently), it's more in the approach and the support that makes the difference, I think.
hth's
PS: and when they come in for a refill, make sure to congratulate them and tell them "hey, you're doing GREAT! look how much they're growing?? in no time, they'll be yours" etc etc" And for any picking or breaks "it's ok, we'll fix it. You'll get the hang of it. I know you can".
It's important to give them that boost and praise them when they do well.
