Just put a few shots through my RXD30Ti in the driveway with a 24” 6.5x47. It has a built in E-brake (or similar) on the end. It was hard to tell definitely from shooting off the tripod into a log nearby if the ports reduced the recoil much over two other cans I took outside to test against (Nomad TiXC and Dominus). Perhaps it was a little softer shooting but nothing earth shattering. Probably not the best cartridge to test this stuff with though, as the 6.5 with 123’s is very mild on recoil.
Then I shot the RXD30 free hand, followed by a few shots with the RecoilX gen 1 screwed on. Couldn’t tell much difference in recoil between the two, so maybe the ports are helping more than I gave them credit for. I definitely noticed the difference the Recoil X made on the TiXC.
Anyway, ports or not, the RXD30 is a great sounding can with a nice low tone. Glad I got it.