If you're thinking of a wind vest or wind jacket always get the vest. A wind jacket always seems to puff up and catch a lot of air. A proper winter jacket is nice but they're typically much more money.

The vest will be a bit chilly if it's 30-35 deg. In those temps I'd want a couple long sleeve layers if I'm doing an hour long crit. I recently rode in 35 deg temps with 2 long sleeve jerseys (ls base, ls thick jersey) and I was a bit cold until I was working hard. I had good booties, tights, gloves, and a skull cap. If I had a neck warmer thing I might have been better. Head/neck lose most of your heat, you can fudge temps a bit by keeping your head/neck warm. Also windproofing is good, even low buck (like plastic bag strips in the sleeves between two long sleeve jerseys).