It seems no one has any data on the 3939C199 batch... I just got mine today with an X58A-UD3R rev2. My h50 arrives tomorrow, I hope to have some results for you guys soon.
Got one from Fry's and returned it because the store I went to wouldn't pricematch Microcenter. Got a second one because upon returning it to another Fry's store they said they do pricematch.
1st one looks like a solid 4-4.2GHz OC'er and cooler. I haven't pushed my current one beyond 3.8GHz, but temps are in the mid to high 70s at load. Have fun OC'ing.