Every serious recorder now records .wav files that will be just fine for your Mac. It's not an issue any more.
Do you want the absolute best possible, into the super-audiophile realm? Or do you just want better-than-CD quality? Does your source require an ultra-low-noise built-in preamp, for quiet sounds, or is it amplified music?
Even a little recorder like my beloved Sony PCM-M10 takes a 16GB microSD card, plus 4 GB internally. That's about 60 mins of .wav recording per GB, or 20 hours total. If you just leave it running the unit will break it into seamless 2GB files, and shift between internal and external memory.
I don't think you'd want an unbroken 16GB file for post-processing because the program might have trouble loading something that big into memory.
My own feeling is that you're better off getting a PCM-M10 and splurging on good microphones and preamp than getting a super-duper recorder and giving it a merely adequate input.