Obviously, opinions vary .. but here are mine on both Wroten and Marshall.
Kendall Marshall - Most likely the best PG prospect in this next draft class. A pinpoint passer and a steady influence on the court. Sub-par defender (not for a lack of desire, just physical limitations), sub-par shooter, and sub-par athleticism/speed are the reasons he's not a projected lottery pick. I've regularly expressed my concerns of him being NEITHER a good shot or having an explosive first-step. I'm a big believer that a PG needs one or the other. I may take Kandall as first PG, but there's enough causes of concern that makes him anything of a sure-bet.
Tony Wroten - Flashy passer. Great scoring instincts (not necessarily a great shooter, but scorer) and nice size along with athleticism. Has shown extremely limited growth in his game over the past two years (I'd call it no growth at all). I've watched Tony since he was a soph. in HS, was extremely high on him, but I've cooled as I've not seen any progress with cutting down TO's, over-penetrating, decision-making, shot, and some attitude as well. Great talent, questionable intangibles.
Of these two I take Kendall hands down.