I have the next one better than that one, and B&S calipers are pretty good. I think that one and mine use the same encoder package, but mine reads out to one tenth (not needed here). I think you'd be fine with them. Some Brown & Sharpes come with an additional plug on the side to hook into a storage device (mine does), and when used right this is a nice addition. You simply setup the zero on a nominal number your after and it'll store all the variations you measure.
The Stoney Point gauges are a little on the long side, and your probably right about the 4" not being long enough. For what it's worth, I hate the Starrett analog calipers (dial type). They're just a pain to reset the zero to the 12 oclock position. The Mitutoyos are the easiest, and you can do it in about a minute. That's one single advantage the digital ones have over the others as you can reset the zero very easilly.
I find that I grab a pair of Starretts (digital) for use most of the time. Mostly because they're close by. But the B&S to me are just as good.
So between the mitutoyo and the B&S which would you choose? Pro's, con's for each? They are almost identical price wise.
keep in mind that I've never owned a pair of digital Mitutoyos, but doubt there's much difference between them. I like the way you can disconnect the battery on the Starretts. But I do like the feel of the Brown & Sharpes (they feel better in my hands). But on the opposite side I like the way the part feels inside the jaws of the Starretts a slight bit better than most, but on the otherhand I like the way the part feels in the Mitutoyo dial caliper better than any of the others. Knowing Mitutoyo's build quality, and they have similar costs. I think I'd probably go the the Mitutoyos. Still I doubt anyone would hardly notice the difference between the three I mentioned. You can also add Fowlers in there and I did get the chance to use an Interrapid for about two weeks. Fowlers are just as accurate as the others, but seem to be a little tough on batteries (I've owned or used several pairs over the years, but they were all larger sized (8" thru 24"). Onething I'd really be interested in with the Mitutoyos is how there battery pack is done. If it has a screw in plug like Fowlers, I'd avoid them. Eventually you'll loose that little end cap. I've probably lost four or five of them over the years. That's the one single thing I like about the Starretts. I have one pair of digital calipers (can't remember the brand name) that you have to remove some very small screws to change the battery. If you drop the screw you may never find it!
Doubt you'll have any buyer's remorse - they are awesome calipers. I have a set, and they are kind of like the first really high-end scope I bought: when it comes it is fun to play with, but after using it for 6 months you pick up your old cheap one and wonder how you ever thought it was good enough.