I've been trying to get a 9mm version that takes glock mags for months. You just can't find them anywhere.
I have one and it has been reliable and reasonably accurate. FYI, Whittakers has two used Sub2K's, both of which take Beretta mags, for +/- $253.99. At least he did last Saturday.
I was having trouble finding a 9 with Beretta mags and wound up getting a Glock one down at Bradis. Can't recall how much, though.