Cheaper alternative magazines - Mec-Gar Kimber Ten II & Bul M5petition 20 Round Pistol Magazine

I don't need 170mm magazines for my 2011, but I did want factory equivalents. I bought 2 as a trial, ran them through the paces a couple of days at the range with a Bul Blaze and they performed flawlessly. A+ for half the cost, and still with an aluminum baseplate...