I went for the Remus ones because I like the hexagonal shape they do and they were half the price of the equivalent Akra's
Now I've got them they sound gorgeous and loud without the baffles in :inlove
I fitted the crash bobbins, the bottom set were easy, though they do crack your shins when you're paddling the bike about to park it! R&G (if that's where you get them from) have a template in the box, which I stuck onto the fairing with blue-tak and then used a borrowed Dremel to cut the holes. I actually chain-drilled the bulk of it and then used the Dremel to grind out the rest. Just take your time over it, follow the instructions, make the hole too small and fettle it out bit by bit, offering the panel up to the bike very often