Several characteristics of longtubes. I can almost always tell if a car has longtubes or shorties because with longtubes, they tend to be quieter at idle, but have a lot more bark at wide open. there is also a kind of echo in the exaust with longtubes. I think lt's sound much better.
I have run shorties and long tubes... the power debate will always be a debate.
The sound the shorties down lower in RPMs will be louder. Around 2000-2500 the LTs will start to sound louder, and up top the LTs will be a good deal louder. The tons is slightly different as well. Is it worth putting LTs on for the noise benefits, up to you, for the power and sound, I thought it was and went with them!