I also downgraded from .167 AT&T to .162 Rogers. .167 has a severe memory leak, which offsets any improvement tradeoffs there might be between the two versions (not that I noticed any) for me.
With .167 I would boot up with 27 MB free, which would drop to 17 MB within half a day (even overnight, not using it). With .162, I boot up with 45 MB free and it's still at 40 MB after a few hours of use plus overnight.
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