Thanks for all the advices. Since my budget is limited, I think I'll get the only unidirectional mic for now as it seems to be more versatile for my purposes. Sound Professionals don't seem to offer the croakie mount for their cardioid mics so I'll probably get one of the CA mics (CA-11 or the new CA-14) + the croakie mount + a battery box. With the free shipping it should be below $200.