At 5K you're in spitting distance of the JVC RS1000, which would be a substantial improvement over both. Might be worth seeing what sort of deal you can snag from a dealer like @Robert_Zohn
@Goducks, two great choices. Sony's VW295 is a native 4K projector, but I also love Epson's UB6050, which is an e-shift technology. Epson's UB96050 is brighter so if you need higher luminance the 6050 is a good choice.
I'm also a big fan of JVC's NX5, which is also a native 4K projector with the best blacks and contrast.