Try some out, but i'd be looking online to get the best deal, the dealer / garden center a stones throw from my house and i suspect the one you have been to service is average at best.
Have you considered a swim spa instead? It is the next logical upgrade i will be taking.
With hot tubs it is easy to get caught with a particular dealer trying the pedal his product, at the end of the day you need to sit down and understand the fundamentals of what makes a good product, and a large part of that is a quality control and filter system including branded pumps.
Also you will need something like a 24 - 32amp feed installing outside and a quality solid base.