Help me choose between these two iMacs.

27 inch mid 2012 $1500

3.4 i7 quad core

16 gb

2tb ata hard drive

AMD 2gb



Or....



21.5 inch mid 2011 $825

2.8 i7 quad core boosts to 3.2

16 gb

1 Tb sata drive

AMD Radeon hd



If I go with the cheaper one it will leave me with more money to go with a better preamp/mic. I'm torn as to which to get and I need to make a decision now. These are the negotiated prices. Both are from private sellers. I will be running protools 11