I have the AWT and AA's versions.
The AA one is a small plastic unit secured via a small hex headed grub screw. The AWT is alloy and clips into place using the mag retainer spring.
Both do the job, the AWT projects out from the side of the breech which makes it slightly easier to roll a pellet into, especially if wearing gloves.
The Rowan single shot loader is nice, probably the easiest of all to use, ie access is easy. Just check that it is properly aligned otherwise you can get the same issues as using a misaligned mag.
Check clearance if you intend using a small objective scope in low rings, basically if the mag fits then the loader should be fine. HTH