Here's what I would do
History has shown that you go with the player with the most upside. They don't always pan out but when you look at Kobe going with the 13th pick, Al Jefferson 15th, Monta Ellis 40th and the list goes on, you see a pattern of young stars and superstars being picked later in the draft. Usually bypassed for the safer pick, the college star.
Of course you can point to the many failed "upside picks" as well so there are surely risks involved but to me it's a bigger risk letting the next Kobe Bryant slip by then it is taking an unproven player. One more obvious consideration is what situation your team is in. If they're a soon to be playoff team maybe the proven player makes sense, and visa versa. see below for more...