One advantage of a longer pole is setting the hook (providing you do not have limbs in your way) I use 5' for tightling and can see how they can be great for shooting docks. Casting is done almost exclusively with a 6'6". I agree that most of the time you have a pretty good idea if it's going to suit you once you hold it in your hand.

Combo's can save you some money but you don't always get qualtiy with it. Junk is junk no matter what it costs and fishing time is too valuable to be wasted with inferior equipment. I say this even though I caught the biggest catfish of my life despite the fact they whole thing probably only cost about $3-$4 brand new back in 70's and the reel wouldn't halfway work. Now that I think about it, it is because the drag didn't work is why I caught the fish.

If you find something you like, pay a little more if you have too, you'll be glad you did.