Be aware: a Hot Spot is not a HotSpring Portable spa. I can't tell you how many times we would have a customer chose one of the Hot Spots, very good spas in their own right, but they thought they were getting a HotSpring.
Hot Spot tubs do NOT have:
Circ pump. This is a killer if you don't happen to like hearing the jet pump kick in on low speed all the time.
All.The.Time. A circ pump is an option on the SX and TX (we charged $200 and it didn't cover our costs).
Multi-filters. They DO have bypass arrangements, just like any other tub on the market, so once the filter gets dirty, it gets bypassed.
One-piece shells. The tubs are acrylic backed with fiberglass. Just like Hot Springs has sold against for thirty years...
Spray foam insulation. They use "Fiber Core," and it works fine. It just doesn't add any strength.
Bottom drain fitting.
Factory fitted Ozone.
Advanced control panel. I'm not saying you NEED an advanced panel, just that the Hot Spots don't have one.
Warranty is shorter - here's the meat of the Hot Spot warranty from their site:
2 Year Shell Surface Warranty
Watkins warrants the acrylic ... surface material of the Hot Spot spa to be free from defects in materials and workmanship for two years.
2 Year No Leak Plumbing Warranty
Watkins warrants the Hot Spot spa against leaks caused by defects in manufacturing and workmanship for two years. This warranty specifically covers leaks from the wall fittings, jet fittings, internal plumbing, internal glue joints, drains, hoses, and all bonded parts.
2 Year Component Warranty
Watkins warrants the electrical components, pump(s), Moto-Massage® jet, and other Hot Spot spa components against defects in materials and workmanship for two years. Some parts, most of which can be changed out without the use of tools, such as filter cartridges, filter lid, spa pillows, and cover locks, are not included in this warranty, but are warranted to be free from defects in materials and workmanship at the time of delivery. Spa covers and other spa accessories are specifically excluded from this warranty, although they may be covered by other warranties. Please check with your Hot Spot dealer for details.
2 Year No-Fault® Heater Warranty
Watkins unconditionally warrants the No-Fault heater to be free from defects in materials and workmanship for two years. This warranty defines unconditional, with exclusion of commercial or industrial use, and improper installation as warranty coverage without exception provided that the component has failed to operate properly within the spa’s system.
A HotSpring Portable Spa has the number 5 in place of all of those numbers 2.
HTH