I went from a Sharp Z10K projector to a Sony VPLHW10 and now have a Sony VPLHW45es. I'll wait until a Sony 4K Laser projector comes down to the $2.5K range before upgrading, which will probably take another 10 years.For projector, I'm currently on an Epson 5050UB, which I acquired a couple years ago (on deep discount sale) right w/in that $2-2.5K sweetspot you mentioned -- I was actually originally planning for 135" screen, but had to settle for 120" now. Probably won't be upgrading that until maybe Epson's(?) next gen of laser 4K PJ (or comparable competition or maybe some new, reasonably affordable flat panel tech that can scale to 120"-plus) in the $4-5K range I guess, which may be another 3-5 years away since they (along w/ JVC and Sony) only just recently released a new gen of laser 4K PJ. Hopefully, that will indeed be my last display upgrade... but who knows?
I'm the opposite. Prior to 4K/UHD I became frustrated about the standard upgrading of catalog titles from the 1970's and up (that I grew up with) from one format to another. I expanded out to content from the 1920's through 1960's and TV from the 1950's and up. A lot of which has slowly been working to blu-ray. I'm finding so much to watch that I've never seen before that I have no interest in rewatching catalog titles I've seen many times, even in a new format (4K/UHD).PS: ...I got rid of 99% of my DVDs and almost never watch the small handful I still have anymore. There's really too much to watch in HD (and 4K) to deliberately go back to those.