[thahemp]

You can get HF cats and get away with not tuning. Worst case scenario... you have a few CELs from the rear O2 sensors. Many have no CELs with HF cat midpipes. I don't have LTs, but I understand that you can expect a CEL if you do those without tuning.

I also noticed that after the Fastlane intake and the Solo HF cats, my car didn't show a CEL, but it behaved weird at WOT with traction control and stabilitrac on. I attribute this to adding up "no tune" mods. Eventually you're bound to cross the line somewhere and your car will let you know. It wasn't terrible, I just turned the traction control off every time I got into the car and the problem disappeared.

If you're going for power, you don't have to pass fascist inspections, and you're going to tune... get long tubes. They are the better value in the long run. With that being said, I was very happy with the performance gains from the Solo midpipes with no tune.

It's up to you.

::EDIT::

And you can run both... but not how you're thinking. You can get long tubes WITH high flow cats. They are a little more expensive. When they call them "off road" on the websites, that means they don't have cats.