I just got one and it is basically a reedy sonic with 40 degree max timing(I measured everything against my sonic). Feels almost exactly the same. But, Reedy starts to wake up at 41 degree timing so trackstar can't really unleash all of it's own potential. But if you have a sonic laying around, running a reedy end bell is a simple fix to the timing limit problem. All the internals are the same except for shims.