I believe Engine Masters did this test, IIRC Snioer doesn't like dual planes, at least not on a dyno. Some claim it was the wrong kind of intake, without specifying what the right kind of intake it should be.
Holley says it works fine. Others say if you remove the center divider it works on a dual plane.

Having dealt with their Projection garbage in the 90's I ain't gambling more money on Holley having their stuff in one sock and remembering to bring the sock too.

So i went Microsquirt.

Running it on my non-mopar. 69 Cyclone with 351W. It runs great. I will admit I didn't do the set up on it and unlike the instructions, it took several weeks for the guy to get it running right. I went with the complete holley setup including distro to avoid issues. Not sure if it created or caused delays but before I did this, tried running 2 carbs on the thing and it ran like crap with a dead zone from 2500-3200rpm.

I believe an open plenum single plane is what those Throttle body injection systems work better with.

That is what all the tuners I've talk to say and advise

My thoughts on the dual plane versus the single plane intake is EFI ECU fuel management based off of one O2 sensor reading from one side of the exhaust system making the injectors pulse the same on both side of the throttle body when the high part of the intake needs a different amount of fuel than the lower part does at the same throttle position
That shouldn't be a problem with a single plane intake

I'm running a sniper on a ld4b intake with a 1 inch phenolic spacer. It's worked really well.
The phenolic spacer also acts as an insulator.

Hello, was looking at trying an Holley Sniper EFI on my 470 street combo. But Ive read mixed opinions on running one on a dual plane intake. Is anyone running this combo with success? I wanted to hear from someone who has actually tried this setup. thanks

Why would you need an insulator? It's a return system.

Insulate the ECU in the sniper from heat transfer.

If that were so you'd think the carbed versions would be stagger jetted.

What I think is that the carb fuel delivery setup is directly tied to airflow thru the carb and, to an extent, it self adjusts side to side that way, at least enough to not be as serious an issue. Whereas EFI sniffs the consolidated output and cannot compensate for distribution issues, seen that on the dyno. 8 O2 sensors show serious AFR differences cylinder to cylinder, TBI or PFI.

That's why those claiming "it works" need to tell what intake they are running and if you're using a spacer. that mitigates the issue. The Weiand Stealth has been mooted as a working intake, internally the divider has a notch which mitigated it too.