Ordered the Intex 28451EP for beside my in ground pool . First unit I got had a issue with salt water sanitation but Wayfair made it right and is sending me another unit .  Hot tub works really well and heats up in 24 hours .   Maintains heat relatively well and loses about 2 degrees per hour .  Recommend using salt or bromine as I tried all 3 options to see water softness .   Salt water also seems to heat the water faster . 

Would recommend if you have a flat area to place the hot tub .  Cleaning will require draining and refill .