I've finally decided to enter the 21st century and give microbore copper
tube a go for some radiators I need to install.

I've just run a couple of lengths of the stuff roughly in place, between
radiator and supply/feed pipes below the floorboards which has
involved some bending around curves etc; next I need to cut off the free
ends to the exact length before connecting them to the rad/pipework.
(I'm using 15-10mm reducers in the TRVs/LSVs, ie compression fittings;
and 15-10mm Yorkshire fittings to the pipework).

Now clearly this stuff deforms extremely easily, but I'm mindful that I
need a perfectly circular section at the tips or my joints won't work.
I've bought one of these gizmos so it will cut cleanly:
http://www.screwfix.com/app/sfd/cat/...21946&ts=05537 but am
wondering about where it's been bent and straightened eg to get round
corners. Is there a way of protecting the ends or something, to stop
them getting deformed during installation? Or am I worrying over much?

Would welcome input from anyone who's experienced with the stuff!

David