Well, INTERESTING! I assumed the F8 was a better match for possibly higher cross-over and matching the 'speed' of the smaller woofer in the Luna, and for smaller size and weight than your other subs. But I now see that the L12 is no slouch in these regards, either, and has the LFE input. I'd be driving the system from an AV receiver.
However, I do also see the L12 caution about higher "perceived noise" using the LFE input. I have had a bad experience with exactly this with a much more expensive Velodyne sub! So now I'll have to ask the benefits of F8 over L12! If there is no benefit in my current application, where might I prefer the F8 down the road? Why would anyone prefer it to the L12?
Let me know if this should now go over to the sub forum.