OP...I'm also running Columbus! Are you starting in the #1 corral? I know the 3:30 pace guy, he's a real good runner, ran 2:46ish at Boston last year. Are you familiar with the course? I know the back half like the back of my hand as I'm from Columbus.
Here's my situation. I ran the 3:15 last fall and had hoped to build on my fitness and take my mileage up to the 65 per week range, but alas injuries plagued me all year so my training has been inconsistent. That said I ran a 1:31 half last week on a tough rolling course so I'm near what I was last year, the major unknown for me is endurance, like I said in an earlier post I really finished strong last fall, not sure that will be the case after 20 this year.
My original plan was to run sub 3:10 in Columbus but based on the above I'm not sure and may also start with the 3:30 pace group (my new BQ requirement)and run the same strategy as last year...though I still may go after 3:10...