So, I recently have been using a KK Zephyr reel and the lightest rod I have until the Sensilite I ordered arrives to throw weightless trick worms and other light baits. I have spinning rods that can easily throw these baits but wanted to dip my toe into the BFS world. I’ve had a good bit of luck so far and catching bass on these setups is a lot of fun. 
  Anyway, I have a couple Revo X and Pro Max reels kicking around since I upgraded them and decided to order a shallow spool for them to put them to use. The KK reel is fine, but feels sort of cheap and like a toy. Thought maybe the new spool in a reel I know I like will be a good option. If not, I’m only out $30. 
  I am wanting to pair this reel with a M/F St Croix Bass X to throw weightless senkos and flukes. I can cast them on standard spools, but when bank fishing, I sometimes need a little more distance without sacrificing accuracy. I really have to throw them hard to hits spots sometimes so I’m thinking the lighter spool will allow me to cast farther without the extra effort and occasional over run… I am basically trying to get BFS casting distance with semi-light baits with the hook set power of a stronger rod. 

  My question for those more experienced than I is do you think this setup will work for casting these heavier baits? Any issues with spool strength? I realize this isn’t really BFS, hence the thread title, but wondering if anyone has experimented with this. 
  Will post my thoughts once I try it out. Thanks. 

Your reels will work just fine on UL, L and ML rods, but has very little in common with BFS gear.

So I’ve had a chance to test out the new spool in a Revo with a weightless wacky rig. I have not noticed a huge increase in casting distance, but can definitely see improved accuracy at the same distances with much less effort. Can really just flick the rod with my wrist and get the bait where I want it. Took some time to dial reel in but now it’s pretty effective. Worth the $30 for the spool and I’m using a reel that was collecting dust so I’m calling it a win.