I recently started using the fine screens, meant for the bottom of the bowl, in the CU, specifically to filter out the finer debris that seems to escape from the holes in the (otherwise fabulous) dosing capsules. There seem to be two side-effects to this: one, the CU stays much cleaner than when using the coarse stock CU screens...and two, the fine mesh screen gets clogged really easily, leading to performance degradation.
I also discovered that removing the CU screen every time you clean the CU is a good idea, as all kinds of crap builds up on the little plastic platform right beneath (or above) the CU screen. This buildup, IME, doesn't seem to be removed by a long CU soak in ISO....so I've started to remove the CU screen every time. This leads to the third side-effect...the CU screen gets degraded more quickly by constant removal, and also, it can be a bitch to clean once a lot builds up on it.
All of this is my long-winded intro to my quest to get more fine-mesh screens. SB includes only one extra per Mighty, so once you replace the coarse CU screen, you're outta extras. I was considering ordering some from SB (they do have a "normal" screen pack that is entirely the fine-mesh ones). But I figured I'd hunt around the house first.
And VOILA....those Firefly 1 screens, that I have tons of, that I never use anymore because I use the FF2 instead...fit the Mighty CU
perfectly.
So, if it hasn't already been discussed (and if it has, I missed it), any FF1 owners looking for fine-mesh screens for your Mighty, CU or bowl, the Firefly 1 screens are identical.