I'm considering doing a DMR build with a version 2 gearbox. I'm planning on using the ICS split gearbox so I can more easily swap out springs to vary the velocity when needed with little hassle. That is to say one upper with a M150 spring and another with a M130 spring, possibly a M140 upper gearbox also. My question, for all you techs and gurus out there, is how well do you see this idea working and do you think the ICS gearbox can handle the strain of a M!50 spring? I plan on making the lower a nice strong gear ratio to pull any "normal" airsoft spring, but I'm more concerned about the gearbox cracking under the stress. As usual, any input would be very much appreciated.