Sorry for the late reply to your message earlier on. I got sidetracked with a particular project and didn't check back with the forums. Yes, GPU rendering has really changed the way I work, specifically for rendering large scenes and more specifically for HD animation rendering, which was almost impossible for me to do years ago. I just didn't want to have to sacrifice image quality for the sake of rendering speed, so I held out on creating animations until a few years ago when the hardware and software finally got to a stage where it was reasonable to do for a freelance, independent artist. Honestly, you don't need a very expensive graphics card, but you do need some very specific requirements from the card depending on the software you choose. For example, most GPU render engines require you to have a graphics card with CUDA cores. This is a creation of NVIDIA products, and CUDA has proven to be the easiest format to program around, so many many GPU enhanced software applications take advantage of this for rendering acceleration. The more CUDA cores your GPU card has, the faster it will perform in software which supports CUDA rendering ( Adobe comes to mind as one major brand which has CUDA gpu rendering, but Blender also supports it). There's plenty of third party gpu renderers which require CUDA too, like Otoy's Octane engine. At any rate, moving to a $400 gaming Nvidia card has proven to be one of the best investments I've made for productivity. The other thing being replacing all my hard drives with SSD's.