cheers guys. some brilliant advice and comments. i have to admit i was expecting lots of positive comments.
i will have a look at the pipes and see if any need replacing before I get it booked in.
if there are any splits in pipes (or other issues), is it just a generic mapping that goes on? if so, can it be done regardless and any issues sorted after without having to go back to sort the map - or does it not work like that?