I guess that depends on the gearing used to be fast at your local track. In my case we run on a tight indoor carpet track and on a large asphalt 1/8th scale track that meeds really tall gearing to be fast. On the larger track the good fan is a must as we are running 2.8-3.0 FDRs.

This is in 21.5 bkinky. But I recon the same applies for 25.5.