Recommending a made-to-measure shirtmaker comes with a lot of caveats, which makes them tough to review. Fit is, of course, paramount, but once you’ve got a well-fitting shirt in your wardrobe, you can take your measurements from the shirt nearly anywhere.
Another awesome writeup by Kiyoshi. A large portion of his success, as he says, is because he’s gone through the MTM process before. Definitely something to consider, though.