Gant Thermal Lite
The sizing is good and after losing my first pair I bought another one for me and my girlfriend as they are very thin but amazingly warm.
The first pair works perfect for spring/fall so down to ~5°C depending on how long the ride is (~30 minutes in my case) and it is thin enough to wear underneath another pair of gloves if necessary.
Additionally which is most amazing to me, even riding in the rain (I am commuting except if it is too slippery to ride) the glove stays reasonably warm, not sure how that works but it does.
I can highly recommend the gloves especially as they are very reasonably priced and I don't want to miss them.