Great replies guys.
Junior and myself have ridden a TM125, RM125, KTM300 (99,02), KX125, KTM 400MXC, 520SX and an 03 125SX.
I hate 125's and I am too heavy (230+). I found the TM to handle the best off road.
Junior is 13, 165lbs and an upper B level rider (top5) Harescrambles. He likes the KTM 125SX for power but got headshake and had trouble in tight technical courses as it wants to be slammed in the turns just like any KTM or it does not turn. It doesnot play ride well. His TM is great all around (older model). Turns well, nice low end as it is a E model with flywheel but still out revs most. Super dependable, Parts are cheap IMO compared to an RM or KTM. The RM and KX are good bikes but after one season they need seriuos work...our TM is gone onto season 3 and is sweet. We should have our New TM125E next week so I will have an update.