Just curious to how much weight the 2/3 version saves.
I've owned my HG 4S cuben just through this winter so I can't give any insight to fair weather use but I agree with Shug, the side pulls don't get a whole lot of use. However they are kinda nice when I pitch very low in storm mode. Stormcrow does offer them on just one side if that would be a good compromise for you. Except for the d-rings they're entirely cuben, my guess is that all 4 probably don't amount to 1/4oz. and having at least one set of side pulls would make the tarp more desirable for resale.
The thing that surprised me going to a winter tarp is that all the extra D-rings add up to more rigging and stakes, next thing I knew I was up over a pound for a 6.5 oz tarp. Eventually, after a few outings, I came to my senses and started paring down my lines and jettisoning various dodads and pieces of shock cord to only what I was actually using.