Perfect size for two adults. I wouldnt pack 4 adults in this - you can, but not comfortable. Take into consideration the water level with no people verse the water level once you add body mass to the equation. Mine warmed up within one day and has kept my temperature setting. Has not kicked a breaker since plugged in and worked well to plug into a normal outlet verse hiring an electrician to hook it up. I have zero complaints. I recommend this product. I live in MI so I plan to drain and store during our winter months due to my fear of the electric bill and what that could end up being.