Wow, what an opportunity for soooo many answers. In my opinion, check every one of your favorite guitar players setup first. Then, hit up their respective pickup manufacturers website. Most companies now offer demos of their pickups online.
Personally, I use an active EMG 81/85 setup which is pretty standard by "enamle removing" guys like Zakk Wylde and Kerry King. But on the other side of the coin, Seymour Duncan offers some great passive pickup combo packs like the JB/Jazz combo that are very popular on a lot of high end guitars and with players like Dave Mustaine.
Like mostly everything regarding guitars, personal preferance is key here. Good luck!