Subrosa. My brother has a $300 Subrosa bike and it is by far the best complete for the price that I have seen. All the bikes have the same geometry as their custom frames. 8" bars, 25t gearing, pivotal seats. If you want to spend like $300 then Subrosa is by far your best bet.
FBM completes are on sale right now. I'm partial to FBM though because I ride one of their frames, and growing up in NY it's good to support a kick ass company that used to build their frames under the skatepark that I used to ride at.
If you're looking to spend more then WTP has some really dope bikes.
Mainly, look for a bike with a frame that is full chromoly (if you're shopping in the $500 range), 8" or bigger bars (big bars are all the rage right now), micro gearing, pivotal seat, something that is relatively light, and probably brakes (riding around college brakeless is fun but bombing down hills and subsequently wearing out shoes in one day is not). Pretty much all completes nowadays are pretty sick so whatever you pick you cant go wrong. Just make sure to look to see where on the bike companies cut to reduce costs (like unsealed wheels, seats with old fashioned guts, bars with weird geometry, etc.)
PM me if you have any specific questions. I've been riding bmx since I could walk haha. Hope that helps!
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