Editing and comparing huge text files

I need to work on several huge text files, each being around 30M in size. The work involves cleaning them and comparing to each other. I have worked with several pretty good text editors before, some are free while others are commercial. For this particular work, I tried ultraedit, emeditor, vedit, madedit, and multiedit. For text comparison, I tried beyond compare and ultracompare. Overall, I would say that the winner is multiedit, for several reasons. First of all, even though all the editors I tested can handle large files, the process is not painless. Most editors show a significant slowdown after loading the files, even on my core 2 duo machine with 2 GB memory. Multiedit does not have this problem. The 30 MB file loads instantly and can easily scroll to anywhere in the file without delays. Second, most editors have very limited file comparison functions built-in, and is not suitable for the work I have at hand. I tried ultracompare, but it did not work in the way it is supposed to, and I gave it up after trying for several times (not a very patient man). Beyond compare delivers good results, then I realized that multiedit has a copy of beyond compare built-in!

The price for multiedit is a bit steep. When most other editors cost around $50 or less, it costs three times of that price ($149). That is probably why it is not used as widely as it could have been...