I just got caught up on this thread after a couple months of not reading.. Here are some comments:
Every projector has it's purpose, and if it fits your needs, there is nothing wrong with using it.
The 6050 isn't exactly identical to the 5050 other than color. It will most likely come with the extra lamp like the 6040 did, and have anamorphic modes. That may not fit everyone's needs, but if you do have an anamorphic lens, you would need either an overpriced Oppo player (assuming you don't already have one), or something like a Lumagen Pro, both of which will cost you a LOT of money compared to the projector price. For people using bigger scope screens that want to watch 4k HDR, a lens is a huge upgrade for the 30% increase in brightness over zooming, and the 6050 would be a fantastic interim projector to help offset the cost of an A-Lens if slowly upgrading your theater...
For those skimming the thread, they weren't comparing $1000 DLP's to the Epson 5050, they were comparing the $2500 4k DLP's, which is a valid comparison pricewise. However, what you gain in motion, brightness, and sharpness with DLP, you lose in lens shift, power zoom/focus/shift with memories, contrast, black floor, color uniformity, and of course RBE. Again, if your main goal is motion and brightness, and you have flexibility in where you mount the projector (at a very specific height and dead center on the screen), you aren't RBE sensitive, and are only running 16:9, the remaining tradeoffs are fairly even. I loved my first DLP projector, I wasn't RBE sensitive, and at the time I didn't need any of those extra features. These days I would have wanted them though, so a DLP was not an option for me.
I had a Sony hw40es, and while I loved it, just like a DLP the 45es is a major feature downgrade from the Epson, with the only benefit being motion and a tiny edge in contrast. You lose 4k capability (makes a HUGE difference on larger screens), all the lens/shift/zoom memories for those with CIH scope screens, and at 1080p, the motion in the Epson is fairly close to the Sony. The 5040 was only a couple hundred more on street price, and I imagine in a few months the street price of the 5050 will drop into the $2500 range as well, making the Sony not really a comparable downgrade IMHO.
As a 5040 owner, if I hadn't already ordered a JVC native 4k projector, I would have upgraded to the 5050 JUST for the 18gbps HDMI. I have issues all the time with the 10gbps limitation. Netflix 4k isn't compatible on some players (Shield plays it at 30p so it is OK), and PSVue is 12 bit color 60p but only 1080p, but this means you have to set your source to 1080p, and then Netflix and Amazon don't detect you can play 4k and don't present the 4k content at all. If you set your source to 4k 8 bit 60p, you get horrible banding in PSVue, and if you set your source at 12 bit 30p 4k, PSVue starts hitching horribly. One of MY big needs is a "set it and forget it" feature set, and the 5040 bothered me every time I went to switch apps.
I did end up going with the JVC, but I can't knock my Epson at all, so the 5050 was a consideration. Tone mapping is a huge feature for 4k HDR, especially if your screen is larger than 120". I have heard that Epson improved their tone map for HDR with the 5050, but it really needs to be dynamic as so many different sources are so different, and one tone map or custom luminance curve just doesn't work for all content. If your only 4k HDR sources are on blu ray, a 5050 with a Panny 820 blu ray player would be an EXCELLENT combination.
Frankly, I believe that most people who compared the JVCs to the Epsons side by side with all other things equal and both projectors fully calibrated would be hard pressed to see any significant difference.
My only complaint was the power supply failure on the Epson. Epson was quick to get me a replacement, but it was disappointing to have that failure with only a few hundred hours on the projector. I hope they have that worked out now on the 5050.
The refurb deal on the 5040 is great IF they have any in stock (they don't right now), but if someone is looking for a great deal on a fairly low usage 5040, my JVC should be shipping this week, so it is likely there will be a 5040 for sale very soon