From what i havenoticed in my own use, is that they grow at the sme rate- but the filing the nile down at the point where the old nail is and the new one will be can be a very brittle poit for nails. And any nail underneath the arylic "shield" tnds to be weker than the natural nail would be.
For me that's a farily eventrade-off, because I have paperthin nails anyway - this is my only way I get any strenght whatsoever. I just have to be careful not to let them get overlong or they break very painfully.
For my daughter- special occasions only for right now. SHe's not allowed to havethem uring cheer bseason anyway - so I;m notnthe bad guy here
Next summer we'll talk about it again.