What tranny cooler for 9.5 Dynamic converter

Dynamic recommends a B&M Super cooler for their 9.5" Race/Street, so I'm wondering what's the best size to get. It will be in a daily driven A body, that will do some track time.
I'm in California so the summers can hit 100-115 Deg, while the winters are never below 30 Deg.

I'm looking at the coolers here
http://www.jegs.com/p/B%26M/758370/10002/-1


I'm kinda leaning towards this one.

Racing Transmission Cooler
29,200 GVW
29,200 BTU
11'' x 11'' x 1-1/2''

Any recommendations?
Is there any problems with going to big cooler wise?
Author: admin