The MGW tool is a well-made tool that retails for $72+ at Brownell's. I got mine several years ago at Brownell's, paying their "trade discount" price of $54. The MGW tool does work well on both large and small frame Glocks. I've installed a lot of sights on Glocks, using the MGW, including Heinie Straight 8's. I filed the opening of the MGW tool and reblued it so that it'd handle the Heinie sights.
I've always used 271 Locite for installing Glock front sights. I've removed several front sights on which I'd used 271 Loctite, and I didn't damage any threads, break off the screw, have to use heat, etc., etc., blah, blah, blah.
For those of you who insist on using Blue (242) Loctite for installing Glock front sights, you'll be happy to know that Brownell's sells replacement front sights for both Meprolights and Trijicons.