well, excaliberpc only sells the 0310s, they don't have any 0308s at all. also, modenaf1, are you sure that they don't overclock as well. my understanding was that the earlier ones did slightly better. BTW, what do you know about the 0302s and the 0307s?
The 0308's, to my knowledge, are just about the best overall. The first week of the DLT3C's was in fact 0307. The 0307VPMW does great with lower voltages, so it's good for air, but begins to yield diminishing returns with higher ones, so its not great for water cooling or higher. However, people are getting excellent results with the 0310 XPMW, so you should have no problems whatsoever with it. The two seem very close to each other in overclockability, and its unclear which week really is better. Just don't get anything that ends in UPMW. These are clearly worse than every other letter code. Excaliber only carries week 0310's now. SVC had 0308's a couple of days ago, but now they have nothing but week 0319's. But all week numbers seem to be doing great, so you should end up with just as good results as someone with a different weeks as yours; its not something to worry about too much. Just go with any 0310 from excaliber.