I thought max came with a number of very good built in render engines.  Mentalray, vray, iray, and all that.  Why would you need or want to render in anything else?  Just curious.  We have Vray in our pipe, but that's only because it's faster than AR.  But now AR is accellerated with Embree, so it's closer, but there's still advantages to using Vray.

The thing I'm most impressed with is how fast you are able to put out quality models.  You're like a modelling machine.  Some of the times you mention for the models in this thread are quite long by my standards, but the topology is excellent, and you always provide great textures.  I'd like to see a video of your workflow some day, and see just how you manage to get your models done so quickly.  I'm sure you can credit some of the tools you use and all that, but I'm sure it comes down to the individual, and how well they know what they are doing.