The K&N I fitted to the Commando is in my opinion, a much nicer answer than the complicated and difficult to remove standard filter.
Some people on the forums seem to have trouble with this conversion, but my bike is all standard but for 270 main jets (260 standard) and I have found the bike runs great with the K&N, no flat spots or hesitation and a good mixture on the plugs as best as I can tell with modern petrol.
The fitment also allowed me to re-position the horrible ignition switch. I did this by cutting off the old bracket from the original bent backplate and sticking it onto the battery carrier with double sided car body tape which is usually used for attaching spoilers and bodykits. I use this stuff a lot, it's very strong and eliminates the need to drill holes. Much better.