I have several of the old style Tapco mags. For the price they aren't bad but there are 2 common problems with them. 1) if you load more than 28 rounds the feed lips aren't strong enough to hold them so when bumped several round fly out of the mags, 2) bullet seating depth is critical. If the bullet is seated a hair too long they will load fine but when the gun is fired they will dig into the front of the mag and cause feeding problems. Once I noticed what was going on no more feeding problems.
TAPCO introduced an improved version that was supposed to address both concerns and incorporates a metal band at the back for lockin. For the money it's well worth it to try one and see if it's works for you.
BTW I have tried the old style mags on both a 580 & 195 series and they worked fine once I figured out their peculiarities.