I much prefer tights worn over shorts. Keeps the important stuff warmer and shorts have a more dependably tight fit. Plus I already have shorts with the exact chamois and fit I like. Why go shopping for something I might not like? Thinking about just the tights, each model of tights is designed for a particular weather condition: temperature range and precipitation. It's good to know exactly what to expect in terms of performance. Website reviews are often helpful. I think zippers are a big deal as they allow one to zip the tights down on the outside of booties, restricting water access to your shoes.
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