if you're talking about Blum hinges
Indeed I am (and that's another bit of terminology I have learned today, thanks!).
Getting the positioning correct was the part of the job that worried me most, but I was careful with my measuring - besides which, the bracket the hinge attaches to allows a small amount of vertical leeway to spare any blushes.
The Forstners really come into their own if you use them in a drill press rather than a portable drill.
This is precisely the thought that crossed my mind as soon as I started drilling...
I bought a cheap set of 5 bits from Screwfix for £7.99. They were fine for the job but annoyingly they have a protruding central guide point, which seems to me to rather defeat the object - I had to be very careful not to drill too deep so the point came through the other side. I note that more expensive models have no guide point and are fitted with a depth gauge. Probably not something I'm going to use often enough to make it worth investing in more expensive parts though.
Anyway, job done, door refitted - and I must say I'm pleased with the job. It even closes properly after making some small adjustments to the hinges. If you're looking
very carefully, you can just about tell the cut edge of the door isn't
perfectly straight. I'll take that.