Some fast and long running fish need stretch in the line.

Mono is great for kings because they make fairly long fast runs. The stretch keeps the hooks from ripping out but more importantly, a king or bonita will run much farther using mono than braid, hence they will be tired when you bring them to the pier. With braid, they will run about half the distance of mono and will come to the pier "green" which greatly increases their chance of breaking you off underneath the pier. If you do use braid for kings or bonita, make sure you have a very light drag. Most pier cobia do not make long runs. They will "bull dog" around the pier and underneath the pier. Braid works well to pull them out from the pilings. Also, they have a tough mouth and braid works better to sink a large jig hook through their mouth. For tarpon, braid is the only choice off a pier in my opinion. You can put so much more line on a reel with braid and it is not uncommon for a tarpon to run 400 -500 yards of line out. I've caught 21 tarpon this summer off Okaloosa Island pier. I probably would have lost nearly half of those with mono. Braid is great for pulling bull redfish out from the pilings as well.

Go with 17lb mono if youre going to use it primarily for kings. You're better off fishing mono in any treble hook application, whether it be plugs or live bait (due to the stretch cushioning against hard runs and explosive strikes). That lack of stretch in braid will cause treble hooks to pull out if you've got one hooked on the outside of the mouth which happens a ton. I also do not like to fish straight braid for any fish with thin or paper mouths such as speckled trout, as you will pull twice as many hooks on them, using braid, as you would if you use mono. The lack of stretch in braid will tear their mouths or open up a huge hook hole with all the head shaking they do. On hard mouthed fish like reds, jacks, bass, catfish, cobia, tarpon, etc. Load it up with braid and have at them. Both mono and braid have different applications and conditions that they excel in. One other thing, on a spinning reel, you'll probably get 20-30% greater casting distance with braid than you will with mono, if that is a consideration that makes a difference to you.

I only use braid on cane poles.

I would use 15 lb mono on your setup and try and to get at least 300 yards on the spool. Keep your drag nice and loose and hang on.

I mostly pier fish in Panama City and use 15 lb mono on my King rod when using a treble hook with live bait. I have a separate rig for throwing XRaps. I have 400 yards of 20 lb braid on it because I can cast those things a mile with the braid and a medium light rod.

I use braid for everything except crappie. I can load way more of it on a reel than i can mono of the same lb test, i can feel bites way better, it doesn’t bow in the current as much as mono, one spooling will last me a few years, and i don’t chafe off on logs and stumps. Powerpro will not dig down in your spool if you put it on tight. I don’t understand whats not to like. I’ve caught plenty of kings on braid and it did just fine. I can also get a braid backlash out of a baitcaster easier than i can with mono.

Braid with a FG knot to a flouro top shot!!

I used 30 lb braid with a mono leader while crappie fishing last week and no I'm not joking.

I agree with Peach. I spool 14 lb. Berkeley big game on all my King rods. The reels
I use will hold 300-320 yds of 14 lb. mono. They are old school Penn 706 ( greenie ) 706z.

Big game is good line for the pier. Very abrasion resistant. There are collectors out there that will give you good money for those greenies.

Can’t give up my Greenies. Kinda like land, they don’t make’em anymore.