G'day hammer. When we were trying to decide on a camper we hired a few before buying.
One of these was the pioneer onyx. These are my thoughts but please note each person has different needs.
1. The company we hired it from have used these for several years as they said for a hard floor camper they were the most robust for their price range. They did spend some time trying to source another one due to the transport cost from manufacturer to Sydney but in the end the ysaid that they could not find anything better.
2. We hired t for 2 weeks and took it out western nsw. In general it went well but we did have some small issues with a dodgy water tap, a bent pole, and a water pump that sometimes would not stop. Nothing significant and again it is not a high end soft floor such as a KK so I think you have to manage your expectations.
3. The basic set up worked really well. Good space under the bed. Functional kitchen. We had several days of torrential rain and gale force winds and we had no leaks.
4. While we liked the hard floor and it was quick to set up for us it showed that a soft floor was the only way to go due to the size of our family (2+3). We travelled with a family of 2+2 and they were also very tight for space. While these are great for couples if you have or plan more than 1 munchkin then be prepared for limited space. You mentioned extra canvas. But remember more rooms means more hassle setting up.
As you can see we thought it was a good camper for its price but not suited to our family. I am sure what ever decision you make you will enjoy your New toy good luck
Ps: FYI this is what we ended up with
http://myswag.org/forum/index.php?topic=17776.0