[Tom Line]

We really like the new AM drivetrain - so much so that after 7 years of building custom drivetrains we're strongly considering using it ourselves. We build out of aluminum stick and channel because we currently don't have any sheet metal capability (though we're desperately trying to figure out how to get it!). Because this is sheetmetal, it saves a substantial amount of space over a thicker 'tube' chassis. It's also much stiffer in a couple directions that the chassis' we normally build.

It can be modified to different sizes per the instructions in the manual.

Don't get me wrong though - ALL the chassis supplied by the different FIRST vendors are excellent options. Each for it's own reason. Something interesting to note with the AM chassis is that the wide version doesn't have a drop center wheel. I haven't measured the long one yet, though I'll do so today.