I am saving the rest of my magazine money for 20 rd. PMags. I really like and own several 30 round PMags, but 20 round mags work better on the bench or ground. I rarely need to burn through 30 rounds - except at an occasional match.
I am surprised that the Magpul 20 round mags will be straight but it doesn't matter to me. I wonder if they will fit some brands of mag wells better than the curved ones have. It seems that people prefer straight magazines over curved if they are going to be 20 round mags. CProducts went with a stainless straight magazine over curved (except for a limited run).
No need to get too excited since "the rest of my magazine money" doesn't amount to much. I won't be the only one buying, though.