It's a bit pricey, but if it holds up it will be worth it. I just got mine today from Brownell's. After fiddling with the first 30 round mag I loaded 11 more YUGO BHO mags effortlessly in less than 10 minutes. It works great, but I'm just hoping it lasts since it's plastic.
Hook the Lula from the front on a full magazine. Same for the tan magazine that you said it doesn't work on, but hold the rear tab with your index finger so that it doesn't snap off.