These are often said to be a drop in replacement for the V-series, but on my V3 the screw holes did not match (but the old where covered by the tuners on the bass side), and they needed a few wraps of tape on the bushing to fit properly. Drilling two new holes per tuner is therefore necessary.
Tuning is so much more precise now, and a deadspot on my G string has better sustain than before, and doesn't seems to have moved elsewhere, so the weight reduction did some good there as well :)