I don't understand why you think cards would be better. Cardioid means heart-shaped. Imagine a valentine with its point at the mic and the wider area unfolding in front. Suppose your instruments are outside that heart shape (which varies depending on the mic--there are hypercardioids that are extra narrow, but none of the internals are hypercardioids.) Omnis will behave much more like your ears....really, aaronji, we don't disagree.
Decide what features are important. If it's battery life, just get the PCM-M10. If it's multiple mic setup possibilities, get the H2N (but be gentle with it). If it's high volume, maybe you should look at the Tascams.
Thank you for your response. Now that I think about it, it's not that I want cards for the sake of cards, but many of the recorders with cards can further adjust the mics' angles or positioning. My main concern is that I'll be using the same recorder to record rehearsals with several musicians as well as to record myself, solo guitar. So to sum up everything up until this point, I have the following questions/thoughts. And believe me, I'm not trying to have you convince me that the H2n is the best choice...I'd much rather be convinced that the DR-05 is the best choice because I'm broke!
1) If I used omnidirectional mics (DR-05) to record solo guitar, would this result in a poor quality recording in relation to using, say, a 90 degree X/Y configuration?
2) When recording solo guitar, would it make any sense to use the M/S feature on H2n, with absolutely no Side mic (thus resulting in a 30 degree angle from the Mid mic only, according to Zoom's website)? Rephrased: Is it correct to assume that, when recording a solo instrument, the narrower the angle the better? Or does it give the recording some pleasing sense of "breadth" when I use a wider angle (say, again, 90 degrees)?
3) If I'm recording a band with M/S, would the ability to adjust the stereo width after the fact give me more control over making sure certain instruments were captured equally? Or am I completely misunderstanding the use of M/S?
4) You mentioned the H2n's ability to simulate omnidirectional mics with its 2- or 4-channel surround sound recording. In the case of musicians spread all around the room, would this be a good choice or is it just a poor imitation of actual omnis?
Thank you.