From the looks of it at VA they are slightly better than the mk x purples, but a bit less powerful than the mk xi purples, though well worth it considering that the mk xi purples require 3 antithoron traces to make (at least the lirpa does, haven't looked at the bat'leth yet)
Hopefully they add these as some kind of craftable, like as the best of the craftable bat'leth/lirpa chain. Also, I wouldn't call it unfair, 1 for Feds and 1 for Klingons.
I was going under the assumption the Lirpa was the normal Lirpa and The bat'leth was a special bat'leth. So I thought the Feds get thier c-store weapon in game and Klingons don't. But I was ninja'd by pics, so I understand now.