I have used both, they are mostly the same. The FF3 offers 2 dot sizes, 3moa and 8 moa as I recall, the FF2 is only 4moa.
Both have the automatic brightness adjustment, the FF3 does allow the user to cycle through brightness options manually, the FF2 has an on/off switch only.
The FF3 I had was a 3moa dot, comparing it to the FF2 at 4moa, the dot size is really a moot point. I have never used the 8moa version.
My personal preference is for the FF2, only because of the activation switch.
The FF2 switch is a slide type and is very easy to use, even with gloved hands.
The FF3 has a push button activation switch and for me it was almost impossible to use with a glove on.
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VAGUNTRADER SECRET SERVICE(shhhhhh, don't tell anybody, i'm undercover)
If you were a hotdog, and you were starving, would you eat yourself?
HEY, we all know that the moon is not made of green cheese. but what if it was made of barbecue spare ribs, would you eat it then?