The Excel Accelerator is also having magazine issues...
First thing a smart owner does is pull out the coil spring and replace it with a oval or squared mag spring...
as the OEM mag spring allows the follower to dip on one end...causing no end of loading problems.
The other headache is the low round count for the mags...frankly, if you are going to make a .22 Magnum pistol,
it better hold at least 20 rounds, MINIMUM.
Otherwise, you are loosing the benefit of what .22 WMR can do as a pistol round.
At the moment, the only .22 Magnum pistol I currently own is a Grendel P-30, the Daddy of the Keltec PMR-30.
It works just fine, but you have to treat it like an AR-15, as in, keep the action CLEAN.
I also polished the bolts of it & the R-31 (Grendel Carbine) to a high shine for better functioning.
So basically, I treated 'em like a Marlin 60 or 795, polish, trigger job, clean, and enjoy
But I'm waiting on the KelTec PMR-30, I want one
And I don't mind getting a 1st run...because I can actually mod it myself if needed.
PLus I'd send back the info of whatever mods were neccesary to proper function back to Keltec so it would help them as well