It really does depend on the person - some people can shrink back down to normal from over an inch, and others (like myself) are still above 1.6 after having them only at 5mm.
The usual concensus is 'If you're not happy to be stuck with it, don't risk it'
Also, the only real difference between weight stretching and plug stretching is that the stretch will go downwards (if you know what I mean) with weights, so the skin under the hole will become progressively thinner. Also, the hole may not end up even.
The main problem with plug stretching is that people don't do it properly. You should NEVER be forcing a plug in to the extent that your ear will tear (bleed) or become raw - your ear is simply not ready to stretch then, and may need an intermediate size.
Teflon tape is excellent, as you can stretch
very gradually (one or two winds a day) so will far lessen your chances of tearing your ear.
