I switched to sperzels on my epi les paul and I'll never look back. You don't have to bore out the hole any more but you do have to drill a tiny hole for this kind of gide post thing they have. But the package comes with a stencil type thing and tells you exactly what size bit to use. Pretty much idiot proof, I've done it to two guitars in 10 mins each and have had absolutly no problems with them.
Edit: Oh yea, and i once broke my low E string during a show, in the middle of the last chorus of the last song of the set. Because of the sperzels i was able to (somehow lol) rip off the broken string and get a new one in and tuned up in time to join in for the last break down. It was something stupid like 30 or 40 seconds that it took me to change the string haha.