Maybe moreso 4.5 but meh, if its got anything to do with The River of Time series it deserves a 5 :) 
 I only saw this yesterday and I so excited, like so excited (like seriously, you have no idea how excited :P) So I bought it straight away from Amazon :) and there's more little novellas coming out!! Awesomeness! 
 I loved being back in their world, and it was great to see some scenes from Lia's POV, particularly her interactions with Luca :D 
 Definitely give this one a read, but go read Waterfall, Cascade and Torrent first, if you haven't already :)