Bought one from them. Love the weapon! It came with only a single mag, so I purchased some after market mags from them. Those mags do not release smoothly! I discovered this at the range when the RO had to fetch a screwdriver to remove the mag! Measuring the mags shows them to be just 0.5 mm too wide and 0.25 mm too thick front to back compared to single mag. It does not drop quickly either, but some burnishing with a dremel and molydisufide have helped that a lot. When I get some more time I'll work on reducing the dimensions of the after market mags.
Be careful out there