Just my opinion. While in the past, I would have immediately been in the "BB the thing" camp, not so today.
To explain, "these days", depending on "how much" power you want, it is more than viable to consider building a small block stroker package engine, especially if the car is originally a SB car.
HP and Torque numbers in the mid 400's are easily attainable, reliable, and relatively cheap on the Small Block, when adding in the extra expenses of the BB conversion, as opposed to the simplistic "re-install" of the SB engine, assuming you already have all the small block pieces on hand.
I still respect the Big Blocks, but when comparing to a "stroked mouse", in the mid 400's HP/TQ, given total costs, and the handling characteristics of the final product, I building far more small blocks these days, just seems to make more sense for the "streeters".
Really sad part, is that the SB based strokers are "running circles" around many BB cars, sad but true !