get a good spinner for throwing tops(I am not an expert in the tuna field but have been there and done that) There are quite a few affordable ones. The 700 will get raped and you will work your butt off to land a big fish on that reel. Casting will be easier and quicker using the spinner, as you do not have to worry about backlashes. I thought about using my 700 matched with trevalla but after having caught a 145lb tuna, i wouldnt pick up the 700 if fish were around. I would hate to hook into anything over 80lbs on the 700 and using anything lighter than extra heavy trevalla will be like fishing with a noodle. If you do use the 700, upgrade the drag.
Affordable spinners are the thunnus, bait runner, Cabo, and maybe the penn 8500 or 9500. If you have tons of rods and reels and cash to spare, I am sure McGolfer has a few good ideas.