And then return the Motion's after they listen to both and save $500. It is tough to compare a tower to a bookshelf even though I have no doubt the Sierra can hang. At almost $1000 per speaker for the Motion 40s I would recommend buying the Sierra Tower - not comparing apples to apples with a 40 vs. 2 - even though the Sierra 2 with the RAAL tweeter is really that special.
RIP Cricket - my pug and little buddy Jan. 10, 2017
Panasonic 60VT60 (cal by DNice)
Ascend's with RAAL, Love my PSA v1800 and a 7.2.4 speaker config, Oppo 203 w/ 2500+ blu-rays and growing. Yes I still have HD-DVDs too.