From your description I take it you are in the UK????? and given that you might be better off to contact one of your registered Corgi installares and check that fact out with them before you commit to the actual boiler purchase.
We have a few Ideal boilers installed down here and have not had any really bad things happen to them that has not happened to any other brand.
Selgas Services Ltd
Craftsman Gasfitters, Plumbers, Electrical Service Technicians