"That will wear out after 2-3 years."
After which, it will cost about a tenner to replace. No biggie!
"freewheel not a cassette which is a disaster if you break it."
Again, about a tenner to replace a six-speed freewheel, bit more for seven-speed. Six-speed freewheels seem to last for an incredibly long time. I don't know how you'd break one unless you were doing downhill MTBing or BMX tricks or some such. I can imagine corrosion being a problem with salted roads in winter. Even if you couldn't get the damn thing off the wheel, a new alloy rear wheel complete with six-speed freewheel can be had for as little as £30. So not really a disaster, at least financially.
EDIT - Seems some cyclists manage to break freewheels and/or their axles/hubs due to "power pedalling". Probably not a problem unless you have extreme Awesome Power and are riding up Redstane Rigg / across a sphagnum bog.