Lululemon Running Tights for Men
My experience with owning running tights is somewhat limited to two winters and two brands; Under Armor and Lululemon with three different models from each. I've tried on a bunch of other brands in stores and returned a few others ordered online. While I have been happy with UA ColdGear® Infrared Run on colder nights and Lulu for warmer weather I am starting to move towards the Lululemon options more regularly warm or cold.
It comes down to fit, comfort and fashion.
For fit and overall comfort the edge goes to Lululemon in my experience so far. The weight of their Full-On® Luxtreme material is a bit heavier and softer than other brands and their slightly thicker cold / wet weather treated options also work really well to keep things warm and dry. The fit is very snug but not compression tight, generally stays in place, and the flat sewn lines run in a way that makes sense to me. I have found that in sizing they can be a bit long. It can be fixed in store for free or as I usually do just worn down over the foot. The waist on newer models does run a bit high, something I hope they will adjust in upcoming lines. It isn't a major problem but can make getting things situated so the crotch doesn't sag a bit tricky.
From the fashion point of view Lululemon has done what a lot of companies don't for men's tights and offer options other than black. It's not that there aren't other colours from other brands but they are often harder to find and usually go completely in the other direction of frantic colour and pattern explosion. The Lulu leggings also match well with their line of 3-7" Surge Shorts if you'd like a little extra layering for warmth, fashion or modesty.
For utility most of the models offer a back and/or side pockets to carry phones, cards and keys which is useful. There is always a drawstring and while they do tend to be somewhat expensive they are comparable in price to other brand options.