I can't (and won't) comment on the Trio, because I have no experience with it! I can only tell you that I am very happy with the Tru-Trak Pictorial Pilot and AlTrak in my -8. They handle turbulence very well, and give a comfotable ride. When I was shopping, I looked at all the usual suspects, and think that any of the top 3 would do a good job. I went with the Tru-Trak for two reasons:
1) The folks that build my EFIS (GRT) have a strong relationship with TruTrak, and have designed their interfaces to work well with them.
2) I liked the Pictorial Pilot's display, which essentially gives me a turn coordinator- should I want to be masochistic and hand-fly partial panel if the big EFIS goes belly up. (But why would I do that when I could just engage the autopilot...?)
Those decisions tipped the scales for me, but I think everyone will have a little differnt perspective.
Paul