Figure it's relevant to post this here.
You may all be surprised to discover that a plastics EZ Shooter, the normal launcher, is around the same strength, if not slightly stronger than a Beyshooter (MFB String Launcher). I tested this with some prong swaps both ways (I had to mutilate a plastic launcher to do so), and the movement of a B tip produced by a plastic launcher is slightly greater than that of a string launcher.
I also tested with a Light Launcher 2: It is significantly weaker than an EZ Shooter, and the MFB Light Launcher is just a joke.
Here's gear tooth numbers:
EZ Shooter (Plastics): 10 Teeth (The EZ Shooter Power Custom should have 9)
Dual Shooter (HMS): 10 Teeth. Identically spaced to the plastics one, as are the ripcord teeth, so the power should be
roughly identical. It also has the spring thing like the spring ez shooter.
Light Launcher (MFB): 16 Teeth (LOOOOOL) Same spacing on ripcords.
LL2: 12 Teeth, closer packed than EZ Shooter (closer teeth on ripcords) Work out what that means in terms of power, but it is certainly weaker.
The string shooter is very different, and has a lot more teeth, but functions very differently, so it's not an valid comparison. But by swapping prongs, I can tell you it is ever so slightly less powerful than an EZ Shooter.
Everything here is done with dragon winders and beyshooters launched as fast as I can:
I used a fake EZ Shooter as I didn't want to mutilate a real one, however I checked all the internals first to ensure that they were identical. I had to shave down the edges of the column where the plastic part that sits under the prongs sit to fit the MFB one on. I then did that, and put on some LL2 Prongs.
I have a fully functional right-spin string launcher to compare to. The modified EZ Shooter causes slightly more aggression in Earth Sagittario DF145B than the Beylauncher, and the steadiness is equal.
The next test was MF-H Diablo Kerbecs BD145MB, the heaviest legal combination as of the time this was posted. The Beylauncher launches it more easily (there aren't really any launching issues for me with Diablo unless I'm using it on R2F, where the extra weight does cause issues with the launch). However, the EZ shooter isn't too uncomfortable, though I do worry about my ripcord. The EZ shooter again gives it slightly more aggressive movement, indicating a higher RPM launcher.
Also, when using plastic prongs on a Beyshooter, it launches plastics noticeably slower. That's a much easier setup to try, too, you just swap the prongs, the plastic part underneath and the screw and you can try it yourself. Benjohadi mentioned doing this and having the same result, IIRC.
So yeah, power wise, I'd say
EZ Shooter Power Custom*>EZ Shooter/Dual Shooter>Beylauncher (MFB)>LL2/L3/L3R>Light Launcher>Hand (only just).
*don't actually have one, apparently there are sometimes skipping issues.