Our stay at the Mantra Portsea was fine. Given the price, we were expecting a little better. We were inforned on arrival that there was no room service and were given a token to use once during our stay to change our towels. The room, again, was ok...but felt a bit tired and dirty. The exhaust fan in the bathroom was almost occluded from a thick layer of dust, the bins and fridge had rust stains and although this didn't effect our trip, the room didn't have a nice feeling, especially for the price.
The included continental breakfast was very average and not worth fighting the other guests for, we chose to eat out every morning.
However, staff were pleasant and the location was very good.
We would recommend this hotel for families, not couples.