I think it is a very interesting model, on every levels, and that you can find some versions at rather better price compared with MSRP.
However, the difference with MSRP can only be determined as good or not compared to how it will evolve in the future, thus I don't think we can know yet.
I also read here and there that the "chin" can become something in the future but:
i) We really don't know: though it is a detail a few people talked quite much about on the net and forums, I don't think that the standard clients who don't come on forums really think about it that much.
ii) Yes, some unique details make a watch valuable but it often happens after a few decades and it has to be compared with volumes.
Like many of the details we talked about when watches are unveiled (the Nautilus and 5170P's diamond set markers, the engravings, the "chin" etc...), people are very critic and seem rather confident but, after a while or after seing it, many change drastically their opinion. Hence, I think we shouldn't listen too much the fuss when dealing with watches (see what happened with the 3700, 5960/1A etc...)
Personally, I could see the 5270 "Chin" (2nd generation) and the 3rd generation with silver dial. There isn't much difference and I must say that when the watch is seen at 1:1 scale, it is not the first thing you see. You see the hands, numerals, date display way before this. I would even say that you mix them easily when trying both watches.
So the "chin" matter is really something that is not a problem to me.
I answer this as I imagine you just wish to secure your purchase as it is never nice to loose too much. However, I personally wouldn't base my purchase on this, even though it has to be taken into account of course.
The 5270 is a great model, its blue dial is casual and classical and nicely decorated. I like the symetry of the information displayed on the dial too. Of course I won't talk about the movement that is the same than in the other references.
Great project, keep us informed
Best, Mark