I think first and foremost you have to worry about your PH, as what Goose stated. All the fertilizer in the world won't help your plot if you don't have the right PH for the type of see you're putting down. I think it's well worth it if you are going to be planting and investing hundreds of dollars on various food plots.
I planted some Whitetail Institute Alpha Rack Plus this year and it came up OK, but that was only due to not having the correct PH. This property just came out of CRP this year so there wasn't a whole lot we could do right to get the PH up. It's not instant. They do have pellatized lime and that works quicker but doesn't stay in the soil as long. So, we planted it and like I said it came up ok but we limed the heck out of the field this fall so hopefully in a year or two it'll be where we want it.
So, get that soil test and go from there!