Best Budget Phono Stage for Clearaudio Emotion?

I am a newbie into the wonderful world of vinyl (Thank you David). I have just started building the system. I have a system that is currently set up for HT, but am adding a turntable to the mix. I currently have a Marantz SR6400 with Kirksaeter Prisma 210's for the front and rears and a Kirksaeter Center. I do also have an APC H15 power conditioner. I will be replacing the receiver in the future to something more analog friendly. I have decided on and will be ordering very shortly the Clearaudio Emotion CMB package that comes with the Maestro Wood MM cartridge and Satisfy carbonfiber arm. I need a good phono stage that will not break the bank. Based upon many threads I have read, I am liking the Cambridge 640P. However, Clearaudio offers the Nano at about $100 more. Is the Nano worth the difference or are there other options at the $300-400 range. Any help is appreciated.