I have had two Tavor rifles.
First was topped with the Mepro21, I liked it but didn't like how the reticle washed out when you were under cover shooting into the bright...
Second one has the full length rail & topped it with a Bushnell Elite 6500 1.25-8x32 & love it.
Neither gun EVER gave me any troubles, I would buy my Tavor again in a heartbeat!
Cheers
Jay
P.S. I can't comment on Pmags, I run with the LAR15 mags...