Lee...Fast68plymouth (Dwayne Porter) is an Indy dealer.

The Indy 426-3 is 6 and 1/2" tall.
The Barton is 7 and 9/16" tall.
The Indy 426-4 is 8 and 1/4" tall.
Measured w/ the manifolds sitting flat on a table.

From my own testing on my 572" hemi, the Barton is equal or better to the Indy 426-3 down low in the rpm range and definitely better up top.
Only downside to the Barton is it's tall and heavy. 10+ lbs. heavier than the Indy manifolds. The Indy 426-3 gets used a lot b/c it's short.
The Indy/Vanke dual plane manifold will obviously be better down low and have better driveability, but at the expense of upper rpm power.

The big Indy 426-4 is a serious piece. My 572 lost a lot of lowend grunt w/ it and slowed down (naturally aspirated) compared to the Barton. It belongs on a serious engine.

Below is a pic showing the height difference b/t an Indy 426-3 and the Barton manifold.