The EBY701 is a very entry display. The contrast ratio on it isn't very good and the viewing angles aren't the best either. I've seen a couple and I was put off by them, I defiantly do not recommend it.
The 629 made some improvements to the EBY701, but its viewing angles are still not very good (the contrast and brightness are great however).
The 669 introduced hdmi input and much better viewing angles. The resolution is also much more flexible and supports up to 1080p.
the HB-RV model is the same as the 669, but with much better brightness (50% better).
the sunlight readable version is a HB version with a coating on it to reduce glare and help make it more sunlight readable.
I wouldn't waste my time on the EB or 629, I would get a 669. I really like my HB version, and never had an issue with sunlight readability.