L/S jersey's - how useful are they?

[Cassandra_Cain]

Hi...

So as the high's are now threatening to sink below 80 degree's, I've officially declared it winter

I've lived in cold climates before (canada, etc) but never ridden in winter. As such I've been happily soaking up all those toasty cold-weather gear threads in these forums. That's given me a lot of ideas about what to try and get in advance. A few questions for you all, please chime in at will

1 - how useful are long sleeve jerseys? TE has some lovely ones like the Bello Vela, LG Pro, LG Athena, etc - are these any warmer than regular SS jerseys? As in are they lined with something warm and cozy or are they just the same mesh-type material as S/S jersey's? I know it sounds dumb but can you roll up the sleeves on them if it gets warmer - or do the sleeves stay 'long' always?

I figure if they aren't any warmer, save for just longer sleeves, than it is probably not worth getting one and instead, opting for a light jacket and/or warm layers over a regular S/S jersey.

I have looked around at a few LBS here but haven't seen any to get some first-hand experience with.