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That's a tough one.... A lot of technology has changed in 20 years just like automobiles...You will most likely gain comfort, efficiency, better Hydrotherapy from better jet designs, whistles and bells and obvious aesthetics. But only you know if you can part with the greenbacks and how much you want the new technology? I personally loose patience and would rather rid a headache than keep throwing money into repairs and I'd get tired of doing them. I'm kinda techy and really like new technology. I'm replacing my almost 6 month old Tub because they made some very kool changes to the new 2014 model....So I'm a bad influence.To get 20 years out of your hot tub is a great success in my book and I'd say you deserve a new one! Yeah....I said it.
The lights for the control panel haven't worked in years so I have to use a flashlight to make any setting adjustments....
I was thinking chainsaw until my buddy wanter the old tub.