I’ve used two for quite a while: A Tascam DR100 mk iii (I think it’s the iii) and an old Olympus LS-100. I also use some Sound Devices recorders from our film program, and they have by the best preamps of anything I’ve used for many years. We have a variety of Zoom recorders too, and. I. Hate. Them. It’s the preamps. Ugh. You won’t notice it recording a band or some such, but for field recording I found these units useless unless very high output mics are used - and then you have to be careful to not overload the preamp. (Caveat: I am really sensitive to hiss/noise.)
The Olympus is also noisy and has a strange un-defeatable rolloff on bass frequencies when using the built in mics, but there’s something about its ergonomics and size. I’ve used it with high output binaural fake-earbud mics and gotten some good recordings.
The DR100 is exactly, as someone mentioned above, a compromise. Far superior preamps to the Zooms (or the Olympus), can be used for film sound in a pinch. We ended up buying several for the film program I used to chair, and a few units had loose switches that needed to be taped down to for filming in very quiet spaces/scenes, but were otherwise fantastic.
One other option I use more and more often: a sennheiser/ambeo “smart mic” headset with an iPhone. I as pleasantly surprised at the results. The noise level is maybe a little better than the Zoom H4n or the Olympus, but its still noisier than the DR100 paired with the right mics. But as an always-in-the-bag phone accessory to pop out for recording at any time, its fantastic. I used to take the Olympus everywhere I went, but increasingly I leave it behind and use the Ambeo/Iphone. The Olympus beats it for speed though - no need to plug anything in, recording level set via physical dial, basically pull it out of the pocket and hit record.
In the end, for any serious field recording (or film sound) I find the mics matter as much or more than the recorders, as long as the recorder has decent preamps.
