@ne_traveling_man, I stayed at two Deltas over the summer in Calgary, and at Kananaskis, and was upgraded on both stays. One to a city/river view on the concierge level (stayed on a cat 5 cert), and the other to a beautiful mountain view with a large loft room with 2 baths (stayed on points). In both cases, they treated us with special care as platinum elite members (including wine and cheese platters). Based on my experiences, I would say you are apt to be pleased.
Delta Hotels have certainly been great additions and we have enjoyed them immensely....that being said, July and August are PEI's high season. Next year is also Canada's 150 th anniversary of Confederation and the accommodations in some cities will be sold out, so while staying at the Delta in Charlottetown will be a great experience, if the hotel is fully booked upgrades may be minimal.
I've had two stays at the Delta Quebec City, one in Ottawa, one in Winnipeg.
My experiences are that many Deltas have a to-the-letter approach regarding the terms & conditions for elite members. Especially in Winnipeg (I was only Silver Elite then) refused to upgrade me to anything bigger than a standard room and repeated I only had right to ask for late check out. (Many hotels had upgraded my room type, especially in the US. Furthermore the Marriott Ottawa had also upgraded me to a spacious corner room and lounge access for a romantic get-away.)
Since then, I'm Gold Elite.
The Delta Ottawa upgraded me to Club Signature level, but would only give me a standard room, despite it being really quiet that day. They did, though, add a fridge in the room (not standard in most Delta Hotels).
Delta Quebec upgraded me to Club Signature level in September, however the room wasn't too impressive, neither the view. I was alone in the room and out for training and social events and day and evening, so I didn't care too much about the room type.
This weekend they noticed I'm a returning client (third stay since the merger), noting I was there in September. Since it was our romantic weekend out and even more so: my birthday, we were given the choice between a suite on the 9th floor with boring view (the patio) or a 'normal' room on the 11th (Club Signature level) floor with a breathtaking view over the city. We chose the second one and we ended up with a very spacious corner room! Additionally I got a 10$ F&B credit or 500 pts welcome gift choice and when they saw me coming in on the second day, they sent room service up with birthday gifts (cupcakes in Delta giftwrapping, 2 mini bottles of ice cider and a big bottle of premium sparkling water). Needless to say, Delta Quebec is becoming my favourite hotel.
I've been at Delta Sherbrooke nearly a year-and-a-half ago, when Delta just adopted Marriott Rewards, but without the option to gain pts/elite nights (only benefits honoured) and they rather asked for the 10$ extra for a higher room with fridge than simply give it to the Rewards member (I admit not having any elite status at the time, but still). On top of that: the Delta Sherbrooke is very outdated; not on par with most of the Delta properties.