im breaking in a brand new vortec 350 with the roller cam and hyperutic pistons, and i was wonder what oil i should use for the break in period, i know that i sould use the gm eos, i have heard shell rotella is not the greatest to use anymore, just wondering, feel free to correct me lol  

Since you used a roller tappet cam the absolute need for added high pressure lubricants in your oil is pretty much gone. It may be of some benefit to a high performance engine even with a roller cam but that it is much more controversial than its necessity to a flat tappet...

Really, any oil should suffice - the SAE tests them all under the same conditions (of course those that are SAE certified, which is everything but maybe some local crap). What I think is more important is that you should change the oil immediately after an initial break-in period along with changing and inspecting the filter.