No to the pregnancy.
I know a few guys are switching over to the diaphram carb because it's getting hard to find rebuildable float type carbs.
Most Tecumseh, "Almost all that you will run into on a minibike" float bowl type carbs have a unserviceable part, there is debate that its either a check valve or some type of emulsion tube that gets stuck/froze up and once that happens there junk. because apparently the carb body is cast around the part.
The advantage with the diapmram carb is that they can be mounted in any position/angle. as where a float carb should be level. And apparently always rebuildable?
As far as performance I don't think there is any difference? But I don't know.
However. In 1970 when Rupp tilted there engine plate they went with a diaphram carb because of the angle. The very next year they engineered a manifold to level out the carb and went back with the float bowl carb....There was a reason, but why? I don't know.
Hopefully MOTRA will chime in, he is very knowledgeable on the subject.
Randy