Having lived in Mondrian for a number of years and my brother in the heart of Westboro for about the same, I can tell you that Centretown is WAY more vibrant than Westboro. Yes, it has a relatively trendy and popular retail strip from 9-5 but in the evenings Westboro is pretty much boarded up.
My friend is in Hudson Park and it is still really nice, holding up well for it's age.
Side note, I visited a patient in the assisted living floor of Vista on Sparks today. Holy crap is that place fancy! They have a spectacular view of the river, Gatineau skyline and Lebreton. Ammenities are top notch (dining, library, meeting rooms, etc.). Not a bad place to live out your days if you can afford it
With the way things are developing in Ottawa, I'd be looking to purchase an older unit in the west end of Centretown such as The Gardens or The Pinnacle. Tended to be nicer quality builds, more sqft and most units well taken care of. With all the highrises in this area there is sure to be more foot traffic, nice restaurants and other services coming soon.