We've had a Dynasty Spa for about a year and a half now and it's been great. It's an Excalibur series Lancelot 3000. The main thing is to drain and fill that thing twice a year (spring and fall) depending how often it gets used.
I buy my chemicals from hot tub essentials, they have a Canadian site and their prices are pretty good. I'd say I pay $50 a year for chemicals. Really depends on the usage though.
You never know what kind of spontaneous hot tub party can happen
Good luck!