I'm pretty excited about the new RSN ships. Although if I had known back in October that Spartan would be releasing all-resin updates of the ships in February 2015, I might have waited on my purchase.
From the renders, it looks like heavy and standard cruisers (Cerberus and Spook, respectively) got updated looks for their 2.0 counterparts (Hellhound and Shrike), along with the escorts. I like the updated cruiser looks--they are beefier than the version 1 sculpts, especially in the middle. The battleship, dreadnought, frigates, and carrier all look the same to me as their version 1 counterparts--may have some minor tweaks that aren't visible in the renders.
But the big news is that they are indeed all resin, and I believe they are all one piece. With the current sculpts, the resin ship bodies (destroyers and up) look fine, but the metal add-ons--bridge, engines, and the fin on the underside--all have issues. The windows on each side of the bridge don't line up, some of the fins are crooked, and I have yet to find an engine piece that didn't have some aesthetic flaw: some nozzles shorter than others, poor fit against the ship's hull, bad mold lines/flash, obscured detail. The frigates and escorts are all metal; while the escorts are OK (at least, the blister I got is OK), the frigates leave alot to be desired. I guess you can get better detail molding in resin than in metal, and the frigates really suffered from being molded in metal.
I do like that they haven't radically changed the RSN ship designs, like Spartan did with the Terrans and some other races. This means that my destroyers, which apparently didn't get a 2.0 upgrade, will still look like they belong to the same fleet as the rest of the 2.0 ships (unlike the Terran destroyers, and I can't figure out why Spartan hasn't updated that model, when all the other Terran 2.0 ships look outstanding!).