We've had two EGYZ144's and the $480 is monies well spent should you want to compete with mid-level 250F riders. Get up in mx class and the guts won't get the glory.
Great investment, post installation is ring every 6-8hrs., piston at 12-16hrs., that's keeping it in race condition. No bottom end issues and its a stock assy so replacement and time aren't a problem.
Should you be racing MX be aware of the new class structures. Lites are now limited to 250 2t's... so the 125 might prove hard to compete in B / A ProSport.
Good Luck, have fun....