Originally Posted by
anainesmusi
The Dawes is a slightly higher quality bike with the 1 1/8" head tube and CF fork.
Whereas the Mercier has a 1" head tube and chromoly fork.
I'm assuming that is an 8s cassette which is ok.
The 11-23 cassette is fairly aggressive, but that is offset a bit with the triple crank. It depends a bit on how strong you are with hill climbs.
According to the web page:
most riders 4'10" to 5'2" - choose the 42 (XSmall) = standover 28"
most riders 5'3" to 5'5" - choose the 46 (Small) = standover 30"
You're kind of on the border with that. The sloping top tubes are a bit harder to judge. I'd probably choose the 46, but you might even consider the 42.
That is one reason why it doesn't hurt to browse around, although it is somewhat rude to take up a bunch of shop time then order online. But, who knows, you might fall in love with a bike at your local shop. And sales occur frequently.