I really don't think any shorty header is worth the effort, they repeatedly show very little gain compared to long tubes.
You should be comparing them to stock manifolds, not long tubes.
One thing to understand is that the milder the engine, the less improvement you will see, with shorties or long tubes.
Another thing to understand, long tubes shine more at higher RPMs over shorties, unless you plan to spend a lot of time at 4500+ the differences isn't as great.
Final thing to consider, how much are you actually going to see with long tubes? +20hp? At $2k that' $100/hp.
