Natural Objects = Definetely Maya Buildings etc. = C4D or 3DsMax. Overall, I prefer Maya significantly.
The difference between dA for tutorials and Pixel2Life for tutorials: Pixel2Life doesn't remove tutorials for copyright infringement(when in most cases, its not - they are just playing it safe), dA does. deviantArt has removed so many signature tutorials, and even Large Piece tutorials because of various reasons - the place has really pissed me off. Though both sites offer amazing tutorials in various fields, your not going to find better tutorials or teachers then from the sources themselves. There are whole communities dedicated to Poser, 3dsmax, Maya3d, Cinema4d, Cool3d(though not a very large one), Bryce, Spazz3d, etc - these are the sites you need to find to learn from, not deviantArt or a tutorial search engine.
