[Old Vantaa Man]

Mate. I'm using Amplitube 2 with an RME Multiface. My old cooker is a P4 2.4 but I get zero latency with it and Sonar if I freeze every guitar track. I can't run more than 2 instances in Sonar simultaneously, which does piss me off as I'd like to play with my kids and their guitars at the same time.
I used Guitar Rig for a while, but it's not a touch on Amplitube IMHO.
I had a Line 6 Pod and also a Guitar Port 2 years ago, but they weren't up to much and you couldn't tweak the sounds after a take.

Edit: I've got a 28 year old Laney 30w combo (my oldestest baby) and some foot pedals here for playing with a band. Wah, tremelo cutter, echo unit.