LondonNick, I lived in Harbourfront Horizon for 6 months and found it good. Though it lacks a bit of 'soul' but you can't expect a place to have alot of it when there is over 600 rooms.
1. yes you can hear people. next door not really but above yes. I could hear people above with high heels at the most inappropriate times but it wasn't so annoying for me to complain but if you have a noisy person above it could be alot worse.
2. yes close at 7pm. annoying. I could only swim in the mornings. Great pool though. Yes 2 hours for lunch. It's not open till march or april too and closes in October.
3. Busiest times you have mentioned. leaves every 15 mins. this was the most annoying as you would have to go out at 5 mins after it leaved to get the next time. i sometimes walked to the station and got the train and that is not good in summer. My biggest annoyance there as transport was not that good. You could walk out and get the bus though to central if you wanted to.
4. I had a couple of minor problems but seemed to be fixed in time.
Though i had some annoyances there it was still worth the time and would not have changed. The view was magnificent and the pool, gym was great. In the Harbourview there was a doorman that was always courteous and very helpful but i found the office staff not so helpful but polite.
My biggest annoyance was the shuttle bus always full at peak times and the location was not convenient for me. I was able to find a cheaper place and more convenient but without the view or services that the Harbourview provided but happier as it's more central and lively.
If you are happy where you are then I wouldn't think of moving just to get the view. You will have everything else and more where you are than what you would get at the Harbourview in my opinion.