http://www.projectorcentral.com/1080p_shootout.htm
Here are how these four great projectors rank on various performance and feature characteristics.

Sharpness/Clarity of High Definition 1080p Images

1. Mitsubishi
2. Optoma
3. Panasonic
4. Sony

The Mitsubishi delivers the sharpest image of the four when the source is 1080p from HD DVD or Blu-ray. The Optoma ranks a very close second and has quite a sharp image as well. The Panasonic and Sony manifest a more apparent softness, with the Sony being the softer of the two.

Sharpness/Clarity of Standard Definition DVD Image

1. Panasonic
2. Optoma, Mitsubishi, Sony

The Panasonic wins hands down in this category, delivering a DVD image that stands apart from the rest. It has less digital noise and ringing than the others. Meanwhile, the other three are essentially comparable.

Deinterlacing of Standard Definition sources

1. Mitsubishi
2. Panasonic, Optoma
3. Sony

There is some real nitpicking going on here. The Mitsubishi is the best of the group, and the Panasonic and Optoma are tied for a very close second. Sony comes in third, but even the Sony is extremely good.

Lumen Output

These readings describe video optimized ANSI lumens in high lamp mode with zoom in wide angle position. Subtract zoom lens factor if lens is in maximum telephoto position (Note: The reason for the radical difference in zoom lens factors is that lumen variances on a given projector generally correlate to the zoom range of the lens, which differs greatly among these models):

1. Optoma: 655 lumens, -6% at max telephoto
2. Mitsubishi: 532 lumens, -24% at max telephoto
3. Panasonic: 500 lumens, -45% at max telephoto
4. Sony: 404 lumens, -25% at max telephoto

Contrast

1. Sony
2. Optoma
3. Panasonic
4. Mitsubishi

The Sony can achieve the highest contrast of the four at the expense of lumen output. The Optoma offers an excellent combination of high contrast and high lumen output. The Panasonic ranks third, and the Mitsubishi has the least contrast of the four. However, these are all high contrast projectors, and their performance is relative to one another. With HD sources, even the Mitsubishi shows excellent dynamic range and sparkle.

Black level:

1. Sony
2. Optoma/Panasonic
3. Mitsubishi

Sony takes first place honors with the deepest, richest black level of the four. Black levels will depend upon calibration, but in general the Optoma and the Panasonic are equal for most anticipated settings that people will opt for. Black level is still quite satisfying on the Mitsubishi, but the picture is a bit brighter and blacks are less deep in optimum calibrations.

Zoom lens:

1. Panasonic: 2.0:1 powered
2. Sony: 1.72:1 powered
3. Mitsubishi: 1.60:1 powered
4. Optoma: 1.20:1 manual

Lens shift:

1. Panasonic: 3 picture heights, 45% horizontal, manual
2. Mitsubishi: 2.5 picture heights, 10% horizontal, powered
3. Sony: 2.0 picture heights, no horizontal, powered
4. Optoma: none

Connectivity:

1. Optoma 3 HDMI, 4 component, 1 VGA
2. Panasonic: 2 HDMI, 2 component, 1 VGA
3. Sony 2 HDMI, 1 component, 1 VGA
3. Mitsubishi 1 HDMI, 1 DVI, 1 component, 1 VGA

Audible fan noise:

1. Mitsubishi
3. Panasonic, Sony
4. Optoma

The Mitsubishi is the quietest of the four, being almost silent. The Panasonic and Sony are very low in fan noise to where it is not a concern. The Optoma is the only one of the four that has enough fan noise to be concerned about. In high lamp mode, it could be a distraction unless steps were taken to isolate and baffle the noise. In low lamp mode it is a bit louder than the Panasonic and Sony, but it would not be a distraction if ceiling mounted behind the seating area.

Current estimated street prices as of this writing:

1. Panasonic: $4,000
2. Mitsubishi: $4,500
3. Sony: $4,800
4. Optoma: $6,800

Warranty:

1. Optoma: 3 years
2. Mitsubishi, Sony: 2 years
3. Panasonic: 1 year
Sigue con un : Summaries and Conclusions que podeis ver en el link de arriba.