Ron,
I've not personally run the RB or seen dynos on it, but if you read that Hot Rod link further up the chain, the b block SD is down on torque compared to all the other intakes. Don't know if it's something goofy with the b block one or not- the article says that the rb version is more highly regarded but they don't give any data to support the claim.
From my own testing, I had more tire spin from idle with the stock intake and 3.23's than I did with the SD and 3.91's on the same engine in the same car, so it killed a lot of tq in my case. YMMV.

I'm 'cheap' too, I've never bought a new intake. Over 10yrs I've grabbed good deals on about 1/2 dozen different b block intakes just to try them out, including the rpm perf. That's the one on the car now (with efi).