I'm a os fan, but will run anything if it performs well. If you are considering the vspec pro mod my opinion is save your money and buy the jx ninja. It's an os and it's a far better motor than the vspec. As for the reedy, what I've seen personally it's a joke. Buy the reedy if you race on a track that has straights no longer than 15 feet. The 150 dollar nova n21b will walk all over reedy. When i see an engine perform no matter what brand, i will use it if it works well. Case in point, definately wouldn't mind owning a nova fms 21-7, but you couldn't pay me to run that weak ass toro nero. Not trying to anger anybody, the proof is on the track. Sit back and observe what runs.