Somewhat frustrating but doable - Podavach OPMOD Magazine Loader

I received mine today and teie to load a few mags with 300blk. I noticed that mine did not have the caliber markings like you see in the pictures. That's not the biggest issue but what frustrates me is as you push the rounds down the curve, toward the mag, the first few rounds tend to roll sideways and you have to pick at then to get back in line. Maybe practice makes perfect I went with this one as it will do all 3 calibers I have 7.62x39, 300blk and 5.56. I may have to try the Mag Feeder by tactical development but it doesn't load AK rounds.