These are not digital mics. These are analog mics and everything that people use on this board, except maybe one or two of us here with extraordinary sums of money, use analog mics. Digital mics are very new technology...and even they use analog transducers albeit with AD (analog to digital)converters in the mic bodies.
The H120 makes hard drive noises, you need to isolate your recorder from the mics itself (run a mini to mini cable from mic to H120) or it will pick up the RAM flushes to the HD (every 2m 10sec if you record in WAV, far less than that if you use rockbox and record in MP3). The SONY mic will overload very easily in loud environments but if you run rockbox it should do it a bit less (rockbox will provide an improved 3.3 volts of plugin power). That other hand made thing looks like its got some Panasonic WM61 caps in it, you still need to isolate it but it should be a little better at handling loud rock than the ECM-DS70P, again you need to run rockbox so it will provide higher plug-in power or else these mics will sound like static at loud rock shows.
What you need is a battery box to provide at least 5-6V to your mics.
This guy, Alchemy, is selling a cheap mic on this board (good reputation):
http://taperssection.com/index.php/topic,78976.msg1050644.html#msg1050644I am guessing an offer of about 10-15 pounds would be fair. It will not overload as easy as the ECM-DS70P but still might overload in very loud situations. Cheap mics yield cheap results.
A guy here named Church Audio has exactly what you are looking for if you can spend a bit more. The sale has ended but I think the regular price is still under 100 quid.
http://taperssection.com/index.php/topic,78199.msg1041163.html#msg1041163AND of course....you need rockbox, the firmware on the H120 makes little glitches every 30 seconds....if you listen carefully, you will be able to hear them.
so get rockbox (it's free and much much better than the iriver firmware)
http://www.rockbox.org