The Kel-Tec doesn't take BHP magazines. I have a BHP and a shitload of 20-round mags for it (and a few 10's, 13's, and 30's) I don't have a Beretta or a Glock 9mm and don't really want one.
Mine takes S&W Model 59 series mags and the full size gun in the middle is an original Model 59. The bottom is a Kel-Tec P-11. The 59 series will take mags from the following models:
S&W 59
S&W 459
S&W 659
S&W 910
S&W 910S
S&W 915
S&W 5903
S&W 5904
S&W 5906
S&W 5923
S&W 5924
S&W 5926
S&W 5944
S&W 5946
S&W 5903TSW
S&W 5906TSW
S&W 5943TSW
S&W 5946TSW
S&W 469
S&W 669
S&W 6904
S&W 6906
S&W 6924
S&W 6926
S&W 6944
S&W 6946
Daewoo DP51
Daewoo DP51c
When I bought it, it was configured for SIG magazines and I converted it to S&W 59 by calling Kel-Tec and getting the S&W mag catch. The Glocks can't be converted to other models until the Gen 2 models but it takes a grip assembly swap.
Mag version available:
9mm : *Glock 17, Glock 19, S&W 59, Beretta 92, SIG 226 *
.40 Cal : *Glock 22, S&W 4006, Beretta 96, SIG 226 *
In .40 caliber. *The Glock 23 has a slightly shorter grip than the Glock 22. *Glock 23 model Subs will take Glock 23 AND Glock 22 mags (13 and 15 rounds respectively unless otherwise modified). *Glock 22 model Subs will only take Glock 22 mags. * Aftermarket high capacity .40 mags such as the Scherrer (sp?) have produced very poor results; there being only a few reports of working out of the bag and only a couple more of working once someone completely replaced the inner springs and followers. *
In 9mm. *The Glock 19 has a slightly shorter grip than the Glock 17. *Glock 19 model Subs will take Glock 19, 17 and 18 mags (15, 17 and 31 rounds respectively unless otherwise modified - note that most 18 mags usually come with the +2 extensions - see below). *Glock 17 model Subs will only take Glock 17 and 18 mags. * The high capacity 9mm Glock mags (Glock 18) work very well as they come from the bag.