Timing Chain vs. Gears vs. ?Roller

on a dual purpose car I would go with a true roller with billet sprockets and multiple keyways for adjustability or just get a Cloye's Hex-A-Just which will cost a little more but is very well built and easy to adjust. If it's a track only car I would go with a gear drive (I love that whine!). You will hear different pro's and con's on the GD, some says it transfers the cranks harmonics to the cam and valvetrain but with most modified engines now running a Fluidampr type harmonic balancer I don't see that being an issue but you might want to ask your engine builder.
And when you hear folks talking about roller engines they are talking about roller lifters.