Early morning pipe is good. A nice, mild English.
McClelland 2015 is a solid vaper.
I've never had the Mississippi River.

I bowl of tobacco doesn't take near a long as a cigar. I say load up the 2015, give it a smoke. Then load up the Early Morning and give it a smoke.
You'll probably lean toward one or the other (this will change on a regular basis, so don't rule out one style based on your preference from a single day).
But I'd pick the one you lean toward now to practice on, as you try to improve your packing, and smoking technique. That way you can pick up changes in the flavor, burn, etc.