I own an Anaconda, a Diamondback, and a Redhawk. I do not have direct experience with the Python so I cannot comment there but I have shot model 29's a number of times.
I cannot discern a meaningful difference in quality between the Anaconda, the 29's I've used and the Redhawk I own. Having said that the Anaconda seems to be more finely fitted than either of the others, the 29's in the middle and the Redhawk a little rougher. They all work just fine although I get my best groups both single and double with the Anaconda.
If you want one I would say go and get it - you won't be disappointed. FME it is a well made, well finished and very accurate handgun.