Looking at a new Creda 890 M, could do with a bit of help, is it worth having the air suspension? it says its "AutoLevel", does that mean on site it levels itself, and if so why is there a hydraulic jacking available, also I assume the standard loo is a cassette type, with a different toilet with holding tank as a 2K extra, if there is not a manhole nearby, do you need buckets or a long sewage hose. Thanks