No dis-respect to Earl Brown and his mods to the front cover, he does a great job with his documentation, but TA has been doing this for over 20 years, starting with the 455 V-8 cover.
The TA cover is machined differently so these mods cannot be accomplished with stock or after market covers. Besides improved oil flow passages, the machining tolerances are MUCH closer for improved flow and pressure, as well as fit.
A few years ago when GM discontinued the Buick 455 timing cover, TA designed an "improved" version, and it has proven to be very successful.
For the last couple years, TA has been machining V-6 covers for parts supplier. Some old "issues" were corrected by TA, and it was quickly realized, that with a little redesign, this could be made into a performance version.
The supplier would not go along with ANY added cost, so TA made the improvements and added this premium V-6 timing cover to their line of engine products.
No one has more knowledge or expertise in the design, fabrication and assembly of Buick timing covers/oil pumps than TA.
So it would be safe to say, the TA covers are by far the BEST available!