if you're going second hand, they you're restricted to whatever comes up TBH.
Only ever heard good things about the piper. Avoid scorpian and milltek.
remind me which one you have fitted again?
I love the look of my Piper but it's a bit loud for me (I'm soft like that). Can't hear it at idle and it's not too bad on the motorway but giving it a bit of welly on the backroads it's a tad on the loud side. IMO of course, like I say - I'm pretty soft when it comes to exhaust noise.
Couldn't say how it compares to any others, only ever had the Piper.