I have the original model with the rear Novak sight. LOVE this revolver! But I do kind of wish they had the adjustable rear model available when I got mine, that's the direction I would have gone. I haven't seen one of the adjustable models in any of the local shops yet, but they are shipping.
Just picked up an adj sight model this past weekend. No time to play with it yet, but it seems like something I might like. Not quite as heavy as it looks. I prefer a S&W, but I had a 4" GP100 a few years ago and always wondered why I traded it away.
I never liked the stacking of the Ruger double action triggers. They are serviceable and durable revolvers, but I like mine to be made in Springfield, MA.
If you're comparing to the "Six" series, yeah, they are a lot better even in a run of the mill GP100. The MC or any polished GP100 will give a very nice trigger feel without that little catch before tripping that the Six series had.