Brad: There is no conventional center section or , wall between the boosters on a twin blade , only between mains and secondaries.
Depending on how one wants to build one, you can have standard 4150 range of boosters or, 4500.
To date, I have never heard of anyone having any distribution issues outside the normal ranges and, often less.

Wilson: We got their full Race port job done on an Indy single plane 4150 max wedge intake , cannot recall the part number at the moment.
What does indy do to it- well, they don't really tell you, but it no longer looks like the intake you had.
I can tell you they lower the floor, raise some runners, change the runners at entry, change the curve under the flange and everything is done by flow/fuel distribution as everything is flowed "with the heads" being there- we had to send the heads as well as intake .

Our plugs are amazingly consistent compared to what we had before porting.
Andy has done the same thing on some of his builds- the 470 build was the first one I had seen- its drop dead beautiful work.

We needed better flow, we needed better distribution and, Wilson confirmed my calculations for 1200 to 1300 cfm needed , not to say more would help.

We have great velocity through the intake into the heads , car is very throttle responsive and, we went from 6.72's to 6.36"s pretty quickly .
It allowed us to change gearing/converter , we added better shocks etc.
We are quite happy with the carb/intake .
Next will be a little head work, different cam so we can get 60ft times down a little more.
we are at 3440 lbs and average a 1.38 60ft, best has been 1.36 but, we didn't get to run in any cold/dry air last fall, might have pulled a 1.34 in good air.
I would like to see the car in the mid to upper mid 1.20's

I honestly don't understand why folks seem so anti something different, such as a twin bladed carb or aftermarket efi etc- imho, innovation is generally a good thing and, the more things people engineer and try, the better things get for everyone over the long haul.

We have been very pleased with our twin bade carb, it does what its supposed to do for us, it runs very clean , idle and driving in the pits is clean, we don't foul plugs etc and we have the cfm we needed.
We have custom built 950"s, we have a Pro Systems 950, we have a 4500 , but rules prevent us running a 4500 and the twin vastly out performs our 950's which are very good carbs themselves.

Hope this helps.
But no, no one that i know of has had any distribution problems with a twin.

blessings.