Best software to convert FLAC to Apple lossless?

I find XLD simpler than Max.

I use MAX as well, with "Full Paranoia" on-always (CD Paranoia error correction). I agree though; it is not the most intuitive interface.

What is the website for MAX?

If you are going the MAC route, why do you want to convert to AIFF or Apple Lossless. Use Songbird instead so that you can play your Flac files with your MAC. No need to convert. I use to convert them with MAX so i can play them with Itunes but now i use Songbird instead.
Have fun.