Unless you use a freight forwarder/US postal etc. you will get slaughtered shipping Acurite to Canada. BTDT. CAOGadgets will ship MUCH cheaper. I guess the main diffs are that:
- WT sensors are much smaller
- several kinds of sensors for both but the WT ones add security, motion, light etc. that Acurite do not
- WT has logging tags where as Acurite does not
- Acurite phone apps are prettier
- WT has IFTTT support; Acurite does not AFAIK
- Acurite has better battery life IME
I have both and like them both. FOr the record my sig link gives me a small referral fee if you buy using it.