10. Whats Important?
You cant select the right mic purely by objective criteria. The most important criterion is sound. Sound is subjective, so trust your ears and dont pay too much attention to datasheets. Large diaphragm microphones are not designed to be ultra neutral or linear. If thats what you want, a small diaphragm condenser may be a better choice. Large diaphragm condensers are supposed to produce a full larger-than-life sound. Thats not something you can express in numbers.
Nonetheless, a few technical figures do give you hints about how usable a particular mic is in typical situations. The most important figure for a condenser mic is self-noise. In pop music recordings, almost any signal passes a dynamics compressor, an EQ or some other processor that adds some noise. The lower noise your mic signal, the more leg room you have for additional processing in the recording chain and/or during mixing.
Maximum SPL is rarely an issue, at least in home recording environments. Mics that reach 130 dB-SPL or more will never cause any trouble in that department. Sensitivity is not a very interesting figure for condenser mics, Their output level is always quite hot due to their internal amplifier electronics. You can safely ignore impedance and frequency response data. Impedance is always low enough on condenser mics; frequency response figures are notoriously inaccurate and dont say much about the actual sound, anyway.
Low cut/hi pass and pad switches are useful extras. Even more useful is a good shock mount.