We certainly have met, acerised
The mods I have done so far:
* Alpha trooper with the basic stuff (AR removal, plunger padding, vent hole sealed, relubricated). Magazine lock removed, but the breech is too wide to easily remove the magazine with the action closed. I see a brass breech in this one's future, purely so I can tactical load.
* Stampede with the basic stuff, heavier spring and 4x 3.7V LiPoly batteries shoehorned into the battery case. Just about to remove the thermal protection and install a fuse, as it is now firing intermittently (which I think is the motor wearing out and requiring more current to start). Motor upgrade in the future, when I find a replacement I like.
The mods that are underway (largely due to unsuccessful prior modding )
* Longshot with brass breech, 14kg (or thereabouts) spring, bolt sled reinforcement, and better plunger padding ... and a smashed barrel guide due to a test fitting with an imperfect alignment coinciding with the epoxy on the sled attachment failing. I think it may have been clunk who pointed out on facebook that my contact patch was too small? Well it was - currently waiting on more brass to build a new barrel. A great learning experience - everyone needs to build a brass breech sooner or later!
* A recon with a 6kg spring, basic mods and all the locks removed. First the plunger failed (despite really think padding), with a really interesting stress pattern on the middle of the back of the tube. So I've got all the internals replaced with aluminium bits (OMW stage 2 kit - hey, it was cheap!), and it is now impossible to prime. Still looking at what I need to fix to get things moving past each other.