Does anyone have experience with the various up-armor kits for MTVRs and FMTVs? How do they compare with dedicated MRAPs in terms of protection and mobility? The MTVR APK was supposed to handle detonations of 12lbs of Comp B (threshold), 16lbs (objective) and 7.62mm all around. I imagine this could be taken further with a custom cab and cargo bed designed to accept armor kits.

It seems like, if you have the option to up-armor your standard trucks to near MRAP protection, while retaining a significant degree of off-road performance, you can buy one vehicle and tailor your protection level to meet the METT-TC.
The MTVR in up-armored config is a beast. It has a higher center of gravity and that has posed challenges with tip-overs as a result of blasts, but that machine can just go and go and go, and it can take bad hits as well, but then again it was already fairly resistant in its basic configuration. I have also been riding in the current M-ATV, and the improved ISS upgraded suspention MRAPs.

The ISS upgrade is a night and day improvement over the old rigid suspension, but still does not approach the mobility of the M-ATV. Serious shortfall remain with both platforms in terms of trafficability, visibility, and any ability to actually fight from it as well as conduct dismounted action.

The M-ATV does has a kick ass communications suite that can be employed and almost puts it on par with LAV-C2 variants. M-ATVs have been able to low-gear themselves out of sand that would swallow any other vehicle, and makes me wish I had bought stock in Oshkosh.