The geometry used on the frame is THE most important part of a bike.
Choosing a frame with a good geo will make your bike feel lighter and will make your riding skills evolve much faster.
On a MTBMX frame the trick is not just short short chain-stays, the position of the BB is what will make the biggest difference wen you hop and spin your bike.
This is our magic numbers, based on a 4" fork.
You will notice that they are very similar on all our frames, even on the Pink full-suspension frame.