Ive run both of those pipes, and they both have their benefits/downsides. Id rather have the Toomey pipe as long as I was running a stock or ported stock cylinder. The Trinity pipe I have on my ported engine now really doesn't start pulling until half throttle. My old Toomey pipe gave me a bit more midrange than the Trinity I run now. I should have kept the Toomey pipe for my now-ported engine.
If you are running a heavily-ported stock top end or a BBK, Id rather have the Trinity pipe.