It is all in the eye of the beholder and what expectations you have, along with you location (which is critical)
To give you an idea, I am using JVC DLA-RS4810, which is not as bright as Sony or Epson.
My HT is 100% light controlled - no windows, black ceiling, screen recessed 2 feet between floor to ceiling equipment racks, with black cloth; walls are dark burgundy/brown color, dark carpet and black ceiling and no reflective movie posters.
Under these conditions, I am using a 150" Elite Screens Lunette (1.1 Cinewhite material).
I calibrated my projector in Film mode, low lamp and yet had to close down the aperture (iris) down to -15, for the image to not be too bright for me.
For my preferences, both the Sony and Epson would be way too bright for my 150" screen.
And contrary to other's reports, including Zombie10K, I see absolutely NO ghosting whatsoever.
This is because I like a cinema like image rather than super-bright, plasma like image, that many others prefer, however, which introduces the ghosting issues.
Thus, what you need to take into consideration and truly fully understand, as you make you projector selection and screen size selection are:
1 - what is your brightness preference level - blinding plasma or cinema like?
2 - your HT room. The less light control you have, the brighter projector you need and the smaller screen you can use.