I buy Knockspell in PDF. I'd get it in print if I had more money to spend on such things, but for now, printing the articles I plan to use off the PDF is good enough.
I would buy Fight On! if I had the money, also. Plan to in the future, maybe get all the issues at once.
For the curious, I play in a weekly 4E game. I also play various older editions once in a while, and hope to do so more regularly.
I agree Knockspell #2 looked really good and has a TON of what I consider great content!
Fight On! #5 finally arrived day before yesterday and I read through about half of it last night. Another issue well worth buying! The layout/presentation has noticeably improved too.