If u have the money and u dont want ground clearance problems then go with the AS&M mids. They have a 1 3/4 inch primary just like all the long tubes but are just a little shorter and are concidered a mid. They come ceramic coated inside and out and come with a ceramic coated off-road pipe. But they are gonna run u around $750 unless u can find a used set like I did

 

I spent nearly a year researching headers. That being said..

Best LT's : Hooker/Jethot/TPIS - Pretty even

Best Mid: AS&M then RK Sport and SLP

Bets Shorty...eh..only as a last resort.

-Dustin-

 

I have had stainless,1.75" SLPs on my car for over ten years. They were jet-hot coated before they were installed. I put them on when the car was new it only has 30K miles now but they have been reliable, fit properly and provide stock ground clearance. They are well made with thick flanges and heavy gage tubing. They were not cheap, about $700 as I recall, but I am glad I spent the $$ because I have had no problems, leaks, welds or cracks.
I do not have any experiance with long tubes and how much extra power is achieved vs. SLP . My car is only mildly modified, Hot Cam kit, headers, and PCM software. Perhaps someone has dynoed with shorties and long tubes and has actual data to help you compare? I suspect long tubes would benefit a more highly modified engine than what I have. I gutted the cat converter and running stock exhaust my car sounds throaty and powerful. Good luck with your project!