Thank you, xtabber, for your very informative post!
So 010 seems to be somewhat superior indeed for people who know exactly what they do (which is difficult when it comes to binary files since e.g. if you search the web for something like "how to edit binary text files in a hex editor without breaking them", you will not get any relevant hits. (From my experience, when you try to replace n characters with n plus x or n minus x chars, it's already broken, even if x is quite small.) The header thing seems interesting, and the running processes thing, too. As for the easy right-click opening-as-binary of (not-running) files, emEditor can do that, too, but it's true, emEditor's "life" licence has become somewhat "expensive", the double quotes being there bec/of 150 bucks being regular price for some other editors just for their current version (which in some cases is not even developed further anymore), so this puts that price into a more favorable perspective, whilst on the other side, most current editors are not priced in that range anymore though.
On a personal note, I own some quite expensive, "programmable"/scriptable editors and did quite some stuff on texts within them, incl. multiple buffers (i.e. files just in memory, not on screen, too), and it was LOTS OF scripting then, bec/I stupidly avoided regex then. Since I've become quite "fluent" with AHK scripting, I finally delved into regex, and I very quickly discovered that for elaborate text processing, 1) regex is the tool of your choice (in AHK: regexreplace is as important as is regexmatch, and this remark applies to any other regex implementation, too), 2) it's available directly both in many editors and programming languages, too, and 3) by the latter, there is no need to shift text bodies from your scripts into an editor to run scripts of the editor's own, then re-export the results, but you can do it all within your scripting or programming language, within both clipboard and multiple variables (instead of the above-mentioned editor-created buffers), onto which you run (mostly) regex commands... and finally 4) that scripting making use of regex will ease and shorten up your necessary scripting to an incredible degree. Oh, and yes, there is a 5) : Special tools, applying regex internally, and presenting some text manipulation gui to the user (TextPipe et al., and then PowerGrep, as the premier representatives of this kind of sw), seem to add nothing to what your own scripting could do in a much more easy way: on the contrary, just as your try (= mine, some time ago) to include some text editor processing into your automated workflow, they just add unnecessary complications (and ain't that cheap, but that's no consideration here). To complete this OT: There is one good idea though that can be retrieved both from TextPipe and PowerGrep: Don't try to complicate your regexes beyond all measure, in order to prove to yourself how smart you are, but be humble and just do 3 or 4 regexes in a row for what you know some expert could have done in just 1 of them: The result is as good as with the 1-regex alternative, with both writing and debugging time minized.
Ok, enough said OT for the rather limited utility of text editors for text processing (= not: text / code creation), it seems 010 (over at bits or full price) is the buy of choice for people needing to work upon binary files (and knowing about them more than I do). ( Well, my original idea was, if you hamper with running processed, you'll very probably get a blue screen - well, let's say you should probably not try to work upon running core Win processes. ;-) )