My experience:
My G17 was acting sub-par with it's PGC metal slide and only managing around 18 shots on green at 260 FPS with TM mags. Installed a Guarder metal magazine catch & tested with WE mags, and the results were impressive. WE mag with the new mag catch gets 55 shots on green at 310 FPS. The TM mags were less impressive but they did get a bump, 30 shots & 290FPS.
Fit just the same as the TM mag's and the finish is good. The baseplates are a little loose compared to the TM but thats just me being picky.
The big difference is in the fill. While the TM mags sputter when they are full the WE mags fill completely silently. They also dont seem to leak as much (if any) gas while filling.
My WE mags are my primary, the expensive TM ones are just for backup... Go figure.
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