8-round mags sould not be causing issues. That is, if you are having a problem, I doubt it's the "extra" round that's causing it. I have not used a 7-round mag, in a gun that will accept an 8-rounder, in about fifteen years, and other than occasional spring replacement - every two or three years of regular use - I couldn't really ask for better performance. Some guns show distinct mag "preferences", and if one brand doesn't work for you, try another. Wilson mags don't lock the slide on my gun(s), so I've been using McCormicks of every flavor and description, and they have worked well. I also like the Novak's mag, which is not a standard, 7-round tube with an extra round in it, but a dedicated 8-round design, like those from Tripp, and the new Wilson Elite. Checkmate has a new, flush-fit 8-rounder than may be the best of all, with a number of features not available on any other 8-rounder. You really have to have 8-rounders, if you want to be competitive.