When I travel and conduct interviews, I use the Neewer CM 28, a curious device that sparks plenty of conversation when I use it, which is an unexpected bonus to warm up interviewees. It consists of two small lavaliar-style mics, a receiver, and a case which is also a battery. Each mic can store 2GB of audio, and the default format is WAV, so the quality is reasonable if a little hollow-sounding. My only issue so far has been that the mics date stamp each file with the start of Unix time (January 1st, 1970), making it hard to match files to interview when it comes to editing later.