Great magwell adapter for the price, did require slight modification... - Sylvan Arms AR-15 f/9mm Glock Conversion Block

So I'm in the process of building a new 9mm PCC and wanted to use a standard AR lower. So after some research and such, decided on this Sylvan Arms Conversion Block (magwell adapter for Glock magazines). Reviews were mixed, with mostly all positive, so I pulled the trigger and ordered it, along with a couple new Glock 33 round mags to use (Leapers UTG GL933 9mm Polymer Glock Magazine RBT-GL933 which are also from opticsplanet.com).

The items arrived and put the magwell adapter an ATI lower that I have set aside for testing before going into a Spikes Tactical Snowflake lower and it went right in. Did have to depress the mag release for it to go in and lock into position, but that's okay. The top button head screw sits against the shelf great and not in the way from the upper being attached. There was a little play in between the magwell adapter and the lower, but that was easily resolved by simply adding a 3d printed shim over the magwell adapter so it sits between the lower magwell and adapter and that snugged it right up perfectly. I also test fit it into the Spikes Tactical lower and it slid right in there as well, not tight and didn't require any force, actually will end up using the shim for that lower as well.

As for the magazine entry into the adapter. It was pretty difficult at first, but immediately noticed the issue. Up top where the magazine stop protrudes out to prevent the magazine from being inserted too far, that was catching and rubbing on the mag. Luckily, it's held in place with the same screw that holds in the case ejection pin, so was able to remove it and simply remove some material from it in a way that it no longer rubbed on the magazine making it cause an issue. After that, mags slid right in place with easy and the mag catch locked right into place and held great. The release also seems pretty smooth as well and no issues.