Hard to take just one rod on a 2 day trip. Hell I'll bring at least 6-8 rods with me on a 2 day trip. Setups will range anywhere from 15# all the way up to 40/50#. But then again some people say I have issues....
But if I had to grab just one rod to start off the day and I not sure what's going to happen then it would be my calstar 800m with an mxj 2 speed with 25#. But then again some people say I have issues....
Yesterday I saw some Sealine SL30s mated to WC Calstars (with tip painted) for the rental rodders. I noticed this because some tourist kept taking my rodholder spot after every drift....and I kept moving his rod back to where he first started at the beginning of the trip! LOL
But I get your point...you want your very own tuna killing stick.
Here's my suggestion then: Sealine reel mated to a low end Calstar or Seeker. Buy one for 20lb and 30lb setups. Next best "bang" for the buck.
In fact, here's one right here!
http://fishingnetwork.net/forum4/showthread.php?t=34550
Ive been on many tuna trips and most boats have decent gear to rent from them. Where do you think the troll poles come from, some guys bring their own but the majority use the boats poles. My suggestion would be to RENT a few rigs on a couple of trips, and see what you like the best. Then you can decide what setup best fits you and make a purchase. This way you don't buy something you don't like.
My two go to setups for Tuna:
Fenwick Inshore rod with AbuGarcia Big Game 7000iHSN
Seeker Classic Series rod with Shimano 4500 Baitrunner.