I'm Canadian myself...residing in Mississauga.
Anyways...couple of things to watch out.
First, this computer is refurbished. I have a friend who bought a refurbished HP computer from Futureshop online that gave him a lot of problems because they did not supply him with any recovery discs. After months of hassle even with HP support which is infamous for its bad quality he ended up buying a brand new PC. So make sure the PC will supply you with recovery discs because if your PC gets infected or etc. and you reformat you will be in big trouble. Also, refurbished means a used PC which has been "retouched" so basically you're buying a used PC for $900.
Second, the RAM is horrible...it's SDRAM. Everything else is fine. I saw one poster noted it is hard to upgrade HPs and that might be a concern but usually I have seen no problems upgrading an HP. Dells are notoriously known for their incompatibility of parts other than their OWN. So if you're a person who likes to upgrade make sure this PC is capable to do so.
The processor is top notch. Very good for gaming. Their GPU is suspect but hardly ANY brand PC will give you good GPUs especially one at that price because a great GPU costs MORE than that PC itself. For example, a 6800 Ultra in Canada costs nearly $1000.
Honestly you can get a MUCH better PC at that price.
Here is a brand...MDG.
They are having a ridiculous sale right now. Also system is upgradable within order at the store. They will give you an upgrade of memory to 1 gig PC3200 DDR400 for $9 and a LCD screen for $9 but CRTs are better for gaming. However their PCs don't give you top GPUs but for $100 (this is not indicated on the site but you can call your nearest store) they will upgrade your GPU to a Radeon 9550 which is better than a 5200XT. Also, I think for another $100 you can upgrade to a P4 3.0 with HT instead of the P4 2.8. I am talking about the Vision CL/2004 which is $997.
Or you can go the pro route which is build your own PC but that might too much of a hassle for a busy person or a person with inexperience.
My recommendation is don't buy a refurbish PC...explore other options. If that is the best option you can find then by all means purchase it. Don't rush into the decision because you might regret it.