I've had this model for a couple of years now. The detail on this model far surpasses Games Workshop's cheaper Trygon. The FW Trygon has dipper crisper ribbing on the chest, and plated carapace armour all the way down the tail and the Scything Talons feature chips and scratches on them instead of the smooth plastic ones GW uses.
This version of my scheme is where I had ditched all the green for purple, and was now experimenting with more bone. I think the increase in bone instantly turns this scheme into something from 2nd Edition. At this point I had also stopped striping my claws and was blending them instead. I was still striping the carapace though.
This model didn't come with a base, so I made one from plywood, polystyrene and mod roc (plaster of paris linen they use on broken arms). Not sure I like it nowadays. It serves a purpose I guess. As you can see it's quite a large model compared to the Grey Knight.