Full HD for 180° view feasable?

Hi Guys,

I need to replace my beamer. In the long term I would like to change from my single Beamer set up to a 2 (or later 3) Beamer set up.
Today I am using an Optoma HD700x in my basement (it's got a 1024 x 768 native resolution). I would definitely change to short throw beamers (~ 4-5 feet distance from front, left, right walls) to fit in my room and to allow for the overhead panel.

I'm not an expert on all the graphics questions. May basic questions are:
- would a Full HD Beamer with native 1080p (1920*1080) resolution generally increase the sharpness and also reduce blurries? (GTX 750ti currently)
- would it also be feasable to use Full HD beamers in a 3-Beamer set up, or would the sharpness be reduced by the warping software anyway?

I could get 2 of these 1280*800 beamers from a friend: IN126ST http://www.infocus.com/projectors/sh...Series/IN126ST
Alternatively this 1080p Full HD beamer sounds nice: Acer H6517ST

What do you think, in which direction I should proceed?

Thanks,
Michael