Irvine 53?
I have one on an Pizzaz, turns an 12.25x3.75 around 13,200 rpm's. Haven't seen an webra 50 run. Have seen an OS 50 run, and it had an lot of power, but also has a higher price tag.
Don't like the fact that they are hard to kill with tx. trim. I like to be able to kill my motors with the trim.