Quite.
I expect you'll find the wet vac handy for sucking up pipefuls of water anyway. They make draining a rad a doddle - you just suck up all the water as it dribbles out of the union. They also empty wc cisterns and pans easily, empty heating pipes so you can solder them, suck up what comes out when you change an immersion heater, and clear air-locks from pipes.
Suggestion - mine's a cheapie too and I use it wet only, without the filter. If I put the filter in it tends to spray water out of the exhaust!
And don't forget the Tesco's bag wrapped round to seal the vac hose to pipe gap.
Yes you can use push-fit but I'd prefer compression on copper. V hot water there and how much do you trust one cheap rubber O ring per joint?? Not supposed to use plastic within 1 metre of a boiler.
By the way - might have been useful to point out that the deposits are to some extent magnetic, so you can do some detection before cutting.
