I recently paired a Diawa Tatula SV TW with a 7ft st croix premier heavy power fast action rod. Question? Is the Tatula a good fit for a heavy or is it better off casting lighter stuff? Performance is great so far been using it for frogs, 1oz swim baits and heavier jigs 

Well you have your answer then!  I use the same reel on a MegaBass Perfect Pitch.

I use that same reel on st.croix bassx 7ft4 heavy power rod.  I bought it for pitching into heavy vegetation.  Mine has the shallow spool 

Great reel for heavier lures, just happens to be able to go fairly light also. I’d be comfortable up to 

1.5 to 2 ounces

I use a sv for pitching flipping and punching. Works great.

I run 65lb braid on my Tatula CT and my Tatula 150 for frogs and jigs in cover. For jigs in lighter cover, I use my Tatula SV 7.1:1 gear ratio. I will use this for skipping jigs under docks which is one of the SV's strengths - set the brake to 20 and keep the tension knob normal where it just begins to click. I could run heavy braid on it as well, I just like 17lb fluorocarbon for jigs in lighter cover situations.

 

Many people think of the SV as a good reel for fishing light lures because of the extra braking, but I've seen many people who use it specifically for heavier applications as well and that's because it skips so well.