Building my first litecoin mining rig. I have two like-new 7970's lined up to buy for $700. Is that a good deal? Or, would I be better off going with another model?
7950's are a good price for the hashing power they put out - and actually put out better hashing power (just slightly) than the 7970s, and are cheaper to boot. I believe, the 7950s run at a lower voltage as well (less power, good hashing). Check the LTC Mining Comparison thread for average hashing power... you'll need to look up voltage and output on your own though to crossreference.
Some of the other experienced LTC'ers can probably pitch in as well.
EDIT: You can get 7970's up a bit higher than 7950's, but I don't believe it's worth the increase in $$.