Besides the fact that I need a calibration tool the guns work as expected. I don't see the problem.
Here are the problems:
1) With 2 guns installed, gun 2 will often get glitchy. swapping guns 1 and 2 does not correct it, the problem follows gun 2, not the gun that glitched. Many people have reported the same results.
2) Calibration is completely positionally dependent. Move the gun position 12 inches in any direction and calibration is off by 2-4 inches on the screen.
3) Calibration takes place on a 16x9screen (for those with typical LCD monitors) but games play in a letterboxed 4:3 screen, so to target the top left of the game screen, you have to aim at the top left of the monitor, which is usually 2-3 inches off the corner of the game screen. Combined with #2, this snowballs into an even worse issue.
4) Most games have an in-game calibration that is required each time you start that game. Outside of mame this can get even more complicated.
5) upon reboot, power loss, or just unplugging the gun, it will get randomly assigned to a new gun # which requires resetting the controls in mame.
6) Outside of mame, most emulators only support 1 gun at a time.
Many of these can be overcome with 20-30 minutes of fiddling, extensive use of third party software, and a deep understanding of what is required to make the guns work well in a game. If you are the only person who uses them and you don't mind doing this each time you start a different game, it is OK. If you are trying to let friends play without babysitting the controls, it will quickly degenerate into a poor experience for everyone.
My favorite arcade game outside of my house is Big Buck HD (or World now), and I wanted to reproduce that kind of gaming experience at home. It misses the experience by 90% across the board. Those guns work on the same basic technology as aimtracks yet somehow work incredibly well regardless of position of the player. I would have paid double or triple for my guns to calibrate and maintain calibration that well. Unfortunately they just don't, so I gave up on them and chalked it up to a $200+ mistake. No front end calibration tool is going to alleviate all the above issues, so it just isn't worth the time to pursue.