The main issue, as usual, is cost.
The least expensive non-Ultra Short Throw (UST) 4Ke laser PJ's are the DLP-1chip Laser from JVC ($3700) and LG ($3K).
Vava has the $2700 UST 4Ke Laser DLP-1.
The prices go way up from here for Laser 4K (4096 x 2160, 8.3 million pixels) and Laser 4Ke (4096 x 2160, 4.6 million pixels), especially for 3LCD and LCoS.
But I am hooked on Lasers. So I can't go back to Lamps.
Another cool thing I've learned about Laser is the half-life. With some Laser PJ, you can do Custom Lamp Power (30%-100% Power). So at 100% power, the Laser should last 20,000 HRS. But when you go to 30% Power, the Laser should last 71,000 HRS.
40% Power = 61,000 HRS (if 100% is 8,500 Lumens, 40% is 3,400 Lumens)
50% Power = 47,000 HRS (if 100% is 8,500 Lumens, 50% is 4,250 Lumens).