Other reviewers are right that these run small--Castelli says I'm on the lower end of their range for medium and they fit me well. But, if you're somewhere in the middle or upper end of any given range, you may want to go up a size at least.
They're snug, but comfy--love the finger tag to help with taking them off. Without those, it would be a chore to take them off at the end of a ride. Padding appears good for what they are--simple (i.e., not gel equipped) gloves. Price was very reasonable. They look well-constructed, but can't yet tell about durability.
I've found these tights very versatile when cycling in the high 30s (F) and into the 50s. They've kept me warm in the high 30s (as cold as I've worn them), are breathable preventing that clammy, sweaty feeling, and have been comfortable in the 50s without overheating. I wear them over padded cycling shorts. I like the elastic waist tie, although the waistband is secure without it.
The only minor negative for me is that they seem a bit long for the waist size (XL). However, they're not long enough to return (better slightly long than slightly short), I'd buy them again (and probably will buy a second pair), and I'd recommend them to a friend.
These tights are a good find.
I bought these tights at an end of season sale and have only one 70 mile ride on them. Overall I like them. The chamois is fabulous; thick and contoured similar to my pro shorts, but orange. The fabric seems warm. Sizing is fine: I'm 6'4' 180 lbs and use a medium. The reason I'm questioning PI is they have done away with drawstrings, zipper leg openings, and the rubber sticky stuff to keep openings in place. The torso is a bit short. So I feel like my back is exposed when I bend over, which you do riding a bike. My solution is to pull up hard on the back, almost like a wedged. The PI tights and shorts from 6+ years ago were better styled, fit better and were better quality.
Got this to replace my old Mortirolo jacket which was getting worn even before being damaged in a crash. Unlike the old one, this doesn't have side vents for cases when temps warm up during the day, but improved breathability should somewhat compensate for that. Felt good riding in low 40s, with a second base layer should be fine for upper 30s. Normally I wear Medium in Castelli, but prefer tailored/race fit - since this is regular fit I was on the fence, but still went with M for layering and worried about being short. It has long cut and sleeves and stretchy fabric so I should've probably gotten Small, but decided to keep M as it's OK for winter. 5'9"+, ~145lb.