A close range interception advice.You know nuking in MMORPG's? Tank and spank?
You can swarm them with 3 stilettos simultaneously with double targeting computers for each.If you are worried you miht lose one, for extra security, add Armor on one of the stilettos, keep the other 2 un-special armored. If you can make the armored one join the firefight a few minutes before the 2 enters engagement range(11% slower for armored fighter), the three +%50 accuracy salvos of AA missiles WILL bring down a UFO very quickly, and perhaps your MMORPG tank (the stiletto with armor) will only be scratched a little.
Of course, this will cost more than the UFO's worth in scrap to buyers, but whatever dents the alien invasion, not just your wallet.