I've been in Canada the past few weeks (and I'm still there). Every carrier has a good selection of Android phones, but every last one of them is locked to the network of the carrier selling the phone. Even the 3g Galaxy Tablets.
They are all perfect matches for the XT network 3g frequencies.
My unlocked Google Nexus One XT flavour has been awesome. I have a Bell SIM in it on a data account. We then wifi tether our phones to the N1, giving us all Net access. Coverage on open ground is about 40 metres in radius. So we can spread out a bit when shopping and still have access.
Unlocked phones are the only way to go.