Sorry man, but no look is ever "here to stay." Some pretty sad looks have stayed around a lot longer then they would have had to because poor saps were just trying to look cool. Some styles/clothing articles have never looked good, but "everyone else is doing it" so they stick around to haunt you years later when your kids are looking through old pictures of you.
Big foot boots, leisure suits, MC Hammer pants, stretch-stirrup pants, and tie-die have all shown to not pass the test of time, while also providing their fair share of embarrassment when a classmate tags you in an old HS photo on facebook.
So don't do it unless you are looking to send the message that you:
1. Don't care too much about looks.
2. Want to be the laughing stock of your kids' middle school sleepovers.
3. Really don't give a crap if girls like how you look or not (come on man, you just admitted that you know most girls don't like it).
There are plenty of looks out there that fit pretty much every occasion with out dredging the bottom (no pun intended) of the current style pool. Sagging might stick around a few more years, a few other disturbing styles have had longer runs. But it's the quality, not the quantity, of people doing it that I'd be looking for. Every Tom, Dick and Harry may have had a mullet in its day, but no US prez ever has. If you're looking to flip burgers or run a cash register, sag away. But if you are looking to gain respect, or impress a girl, show a little more care in your appearance.