I don't think there is too much to think about...they probably are both good for the job. I personally would probably go for the NAD, but its not a huge decision.
opinions
I have the chance to purchase either a Nad 3020 or a Sansui 666,both have been professionally serviced,I use the amp primarily to listen to vinyl which is played on a Rega turntable and i have AR 2x speakers,what are the pros or cons of either of these amps,thanks in advance