The Colchester Student weighs about 3/4 of a ton while the Bantam weighs about 0.5-0.6 of a ton, this one can be moved with a little difficulty by one person. I have moved a few of these machines, it is not difficult as I can lift the light end (just!) while two people the other can slide it. They can also be moved on rollers but it is faster on concrete to use either an engine crane or a pallet truck. If you have a gravel drive some thick ply is a must or you have no hope of shifting it.
Lathes this size come in handy for skimming brake drums and shoes while a Myford/Boxford are too small to do jobs like these easily if at all. Many chucks have been damaged by trying to turn too larger job, it breaks the scroll inside the chuck or the jaws themselves.
The bigger the lathe the bigger the cut but there are limits!
There is a benefit to buying a three phase machine, they are cheaper because home users rarely have three phase though I do. Some larger lathes were made in single phase but these are rare.
Older motors DON’T run well on converters (which can be unreliable) but they will run perfect on an inverter. The difference between true three phase and a converter is very noticable in both the noise the machine makes and how well it runs. A couple of lathes have run terribly on a converter yet run perfect on true three phase. I had a Bridgeport milling machine on an inverter, ran smooth as silk from a 13a socket! You can burn out the suds pump motor on a converter, only run this when the main motor is running. If the load on these is wrong damage can be done which could get expensive.