SCOTIA BANK-Canada & Mexico

Getting plain info from WISE is like pulling teeth. If I understand, I would open an account in Canada with WISE, deposit Canadian funds with them, which they immediately convert to the currency I choose, at then current rates. Then, I would use my WISE card, (which is obviously a debit card) to withdraw pesos from ANY ATM in Mexico (at least that's what WISE promises).
Presumably, I would have to pay an ATM fee, which can run anywhere to $3 or $4 Canadian per transaction, (30 or 40 pesos?).
The advantage, using a WISE card, would only be in getting a better currency exchange rate than the regular brick-and-mortar bank offers.
(I'm assuming that the currency exchange rate I get would be the rate in effect at the time I loaded my WISE account with Canadian $, which WISE converted to pesos at the time of deposit....perhaps weeks or months earlier. Have I got that right?)
If I'm right, it would be best to deposit into the WISE account when the Can $ was strong against the peso, to lock in a good rate.
If I'm wrong, and WISE withdrawals are based on currency exchange rates in effect at the time of ATM withdrawal, then the WISE advantage depends soley on how much better their currency exchange rates are, than the "big banks".
I use my Canadian Scotiabank debit card at Zihua's Scotiabank. As a result, I
pay no separate ATM fee. The currency exchange rate I get (NEVER accept the offered rate) routinely runs 2.5 to 3% LESS than the quoted mid-market rate shown on websites like xe.com
So, for WISE to make sense for me, their currency exchange rates would have to be significantly better than the 2.5 to 3% premium off the mid-market rate I usually pay, and including the obligatory ATM transaction fees.