I had one years back and didn't like it...but I have a larger tank now and carrying a 5 gallon bucket back and forth (both for taking out and putting in) gets old. I had to get the 50 ft cord one due to location--make sure you get one that has extra length as you don't want a taut hose stretching across the floor.
It really is great for putting water back in. That said, you could just buy a potable water hose (like for campers) and use that to put water back in. Get a Python if you *also* need to take water out, otherwise I'd just get the hose as it is cheaper.
I'm iffy on the "take water out" part. I can't get enough suction to pick stuff up like I can with my siphon cleaner. So what I have been doing is to do one bucket's worth with the cleaner+bucket, then the rest with the Python just sitting there sucking water out. My tank is lightly-stocked so this works well, with one bucket I can get most of the visible stuff. Then you just change the setting on the faucet connector and you are ready to put the water back in.