It's hard to decide how many stars to give as Rivergrove has many positives and negatives, but hopefully this is accurate enough.
The positives:
Recently renovated so everything inside is new, shiny and well-kept.
The pool has at least one lane open from 1-7 during the week
The gym is big, more equipment than most rec centers, and as I said - everything is new
The change rooms are fairly clean, though I'm not sure that part was renovated.
The negatives:
Depending on the time you go, there is one lane open for swimmers of all levels. This means you may go planning to swim laps and there's somebody in the lane who just wants to tread water and chat up the lifeguards. The lanes are pretty narrow so this can be very annoying.
It's always busy - it's located in the hub of a large suburban community (the whole point of Rec centers, I know). So there is almost always a line to gain access. Even if you have a monthly pass, you can't sign in yourself (though you can bypass the line)
There are only two private change rooms in the locker room. One is massive and one is tiny. Good luck if you get the tiny one.
Overall I do like Rivergrove and would go more often if it was closer. As it is, I'm usually there 1-2 times a week anyways.