I have Tripp Cobra, Wilson 47d and Wilson ETM 8rnd mags and have no issues with them. The WC ETM mag was designed from the outset to be an 8 rnd mag with a longer tube. This makes the ETM easier to seat on a closed slide and compresses the spring less that may lead to increased reliability.Other than 1 rd capacity difference between 8 and 7rd mags is 7rd magazines more reliable or really no difference?