Having compared the two (w7000 vs. w1070), well the w1070 does have more dynamic color (intrascene contrast) when the IRIS is not needed (in all but dark scenes), but the w7000 can go darker sometimes (but the w7000's IRIS is far from perfect).
I would pretty much say that the w1070 and w7000 are too different and too similar at the same time to really consider one better than the other, it just depends what you are doing with it and what your needs are.
Benq w7000 Advantages:
For HTPC text or reading, the w7000 is sharper and has a more uniform focus (at least between the two samples I saw).
Not as loud overall and you can mount it farther back
Does not require an ND filter if the image is too bright (the w7000's IRIS can bring the brightness way way down to any level you need)
Definitely has a 6-speed adjustable color wheel, though in 6-speed mode the color wheel is so loud that you probably will use 4-speed
Has Frame Interpolation in 2D and 3D, but does not support 144hz 3D like the Benq w1070
Much better placement flexibility, and has center lens shift vs the w1070's offset-based lens shift
Works better with the Da-Lite High Power screens or any retro-reflective screen due to mounting flexibility
Lamps last fairly long even though only rated at 2000 hours, I am approaching 3000 hours and my lamp is still bright enough on a 106" 1.5 gain screen
Benq w1070 Comparison
Uses Dark Chip 3 instead of Dark Chip 2 which essentially allows it to have better intrascene contrast (w7000 = Dc 2)
More accurate color OOTB than the w7000, though the w7000 is not that bad either OOTB
Color Wheel speed does not appear to be adjustable, therefore 4x might be the maximum (though might be 6x, I do not know for sure)
Supports 144hz 3D which reduces the shuttering / flickering effect for some people relating to the DLP Link glasses
Does not support Frame interpolation in 2D or 3D (some prefer FI for Sports)
Often too bright in 2D for smaller screens, an ND filter will be needed
Has no IRIS and no really dim modes for dark / night-time 2D viewing (which is why you need the ND filter)
Uses lamp dimming tech instead of an IRIS, which I find has very little benefit
Lamps will likely last a bit longer, they are rated longer and I think use less wattage, plus this PJ is brighter in BEST mode
Overall in videos (2D anyhow), the image is more similar looking than it is different, you'd be hard pressed to see a difference much of the time. It's hard to say which one is better, they are too close to call. I would say the w7000 is not worth the extra price unless you do a LOT of HTPC reading and are really picky about focus uniformity (I am so the w7000 was worth it to me), or if you are picky about audible noise (then get the w7000), or if you want Frame interpolation (another reason for w7000).
Otherwise, the w1070 does just fine.