To me the Aries is just an overall superior product. The fit and finish on my Aries is just in another class compared to the Scout I owned. Socially, the difference to me is that the Scout was a bit hyper fast. I liked it but it was ultra dynamic. You may like that.
The clarity, detail, bass, and smoothness of the Aries is amazing. I think the advantages of the scout (speed) have to do with the 9" arm. The 10" arm is just more accurate to my ears. If you want the best of both worlds get a fast cart on the Aries (17d2, Clearaudio etc) and enjoy.
Bottom line, the Scout is a superb starter table. It make sit clear that analog is far superior to any digital source. The Aries (with the longer arm) makes the comparison to digital laughable and the comparison to the Scout makes it look like a starter table.
Good luck
Vik