I bought in CityPlace about 4 years ago, after telling my real estate agent that I was not interested in anything in CityPlace.
I walked into the unit and it was everything I was looking for. The layout was great, the finishes were everything I wanted, and the price was perfect.
I have absolutely nothing bad to say about it. I recently lived in Liberty Village for a year and did not like it at all. I recently moved to upper Jarvis so no longer own property in CityPlace, but definitely have nothing against it. I only left due to a breakup, and would still be there if it wasn't for that. I disagree with going for the new builds, as they are overpriced and much smaller.
I lived in Luna (25 Capreol Court) and had a good experience in that building.
Being right near the Gardiner is a convenience (I too go to Mississauga frequently), and being close to the 504, 510, 509, and 511 makes getting around the city easy. The Eaton Centre is also a decent walk from CityPlace in better weather and I usually just walked there whenever I had to go. From Liberty Village, its much harder to leave and get back, whether you use transit or drive.