The problems on your YFA sound like there´s something wrong with your acceleration pump assembly- maybe a faulty pump diaphragm or a accelerator rod thats just outta whack.
You mentioned the sputtering and stalling on sudden acceleration only; how is it running on consistent part throttle (sustained highway speed)?
Concerning the RBS,I always liked it for its simple, straightforward design.
Like on most bigger Carter carbs, there are no gaskets below fuel line, the casting is made of an aluminum-based alloy which resists corrosion and distortion better and dissipates heat faster than zinc-based alloys (zymac).
According to the Falcon Handbook the RBS is rated at 215cfm which is at least 5cfm more than the biggest 1.29"-venturi ´69 autolite 1001, or 20 more cfm than your YF.
The downside of the RBS usually is its incompability to most air cleaner bases (reuse or get another original air cleaner assembly) because of the wider carb neck and choke height, which potrudes through the air cleaner base line, thus demanding a mushroom-type- air cleaner which is offset to clear the choke mechanism, but drops down behind the choke ass. to lower the filter element position and allow hood clearance.
The RBS´ throttle shaft linkage consist of a hole drilled into the throttle shaft lever and usually can be converted to any type of linkage - if you want to stay nostalgic, ball joints should be available through auto parts stores and some hardware stores. If you have trouble finding them anyway contact Lokar or any daimler-chrysler dealership that supports classic mercedes-benzes.
