I am considering buying two 125 pit bikes with the 12/14 wheel combo. These will be used mostly for teenaged kids to trail/logging road ride with the occasional backyard BBQ "national mx" . I was wondering about the reliability of these mid priced units. I'm considering the SSR 125E or Pro B2 models, they "LOOK" to be a pretty good bang for the buck. Are some of these engines more prone to breakage, ie shift/gearbox , kickstart, clutch etc? I see where some bikes are neutral start and others are start in gear. Are the newer designs the start in gear style? Parts availability an issue? The frame and suspension systems will have wear items. Can you get parts, stock or aftermarket? I could buy fairly used TTR's for the same price as these Pit Bikes and you can get Yamaha parts easily, BUT, these Pit Bikes look like a heck of a lot more fun!! Thanks in advance for your enlightenment !