Charles S.wrote a review of Castelli Perfetto RoS Glove on December 13, 2019
Familiarity: I've used it once or twice and have initial impressions
All right; thought I would add to the review pile for this one because I'm very impressed after one wearing. I am very particular about gloves because once my hands get cold, they take a long time to warm up and I get very uncomfortable in the meantime.
I used these today for the first time; temps were about 45, and they kept my hands warm throughout my 90 minute ride. I could really feel the insulating properties of the Goretex because when I upped the effort level, my hands would get warmer; which has never happened to me with any glove before. In fact, when I stopped mid-ride to talk to someone for a few minutes, my hands got warmer. They are very thin so you really do get a good feel for your bar/hoods/etc. In fact, I think they could be improved with maybe a millimeter or two more padding in the thumb/forefinger area to give you a bit more cushion where you grip the hoods, but this is a minor complaint. Based on my feel today, I think that I'd be comfortable down to about 40 Fahrenheit with these; but again, if you're really cranking out the watts, they might be good for high 30s; we'll see.
One thing to keep in mind is that the fabric around the wrist is very tight and doesn't run very far. So the result of this was I felt some wind coming up my jacket sleeves. Not a big deal at 45, but probably more of a factor at very low temperatures.
Recommended if you're looking for a thin, warm glove that gives you good tactile feel of your bars/hoods/etc.