Re: Changing to SSD is a one-way street!
It depends a great deal on your use pattern and hardware. I rarely reboot, so boot time doesn't interest me and Win8.1 greatly improved caching and memory use so most of my tools are sitting in RAM whenever I need them - I don't actually feel much difference after switching to SSD!
More surprising, I added one primarily to help with massive compile jobs, able to max out 6 cores continuously with 100k's of files being processed. Again it's hard to tell if it's helping, The 12 core office build machine wasn't noticeably drive bound either on the same job.
For my work load its obvious throwing 32Gb RAM at it is more effective than a fast 500Gb SSD. Nice things to have but I'm not seeing the magical improvements many claim. Probably much more effective on the low end systems most use though.