Most cheap converters are made from v6 or 4 cylinder cores which makes them smaller and stall at a higher RPM when put on a v8. Their cases and internals were designed for lower HP applications.
Here you can compare this cheap coverter
http://www.transconverters.com/ebay/...age3bottom.jpg

Here's a PI vigilante converter
http://www.converter.com/images/prod...igilante-1.jpg

As you can tell the Rev max converter Looks like they've welded on a ring to the converter so it will fit the bolt pattern of the V8.
Compared to the PI converter which is made custom by PI not by using a 4 cyl or v6 core to make the converter.

Well they say there:

Completely Tig Welded Reinforced Impeller
Tig Welded Reinforced Turbine
They use a TCRS Robotic Welder

No furnace brazing


If you guys do a google search there seems to be some info. on these in the Diesel truck world...though even there revmax is also fairly unknown.