They might use the same makers in the Netherlands (or not, the pictures could come from anywhere), but the process is decidedly inferior. If your custom suit doesn't fit you need to 'get it altered at your expense and record the changes so we can get it perfect next time?' Seriously?
To be fair, that's why KW suggests getting the trial suit first, decide what alterations you need and return it to get a new custom suit.
"Unlike other custom tailors, we prefer to first send you one of our ready-to-wear suits for you to try on, and then you can note measurement modifications based on that (e.g. +1" waist, -0.5" sleeve, etc.). This allows us to have a very good chance of making your first suit fit perfectly. Whereas the more common method of simply submitting a set of measurements typically results in ill-fitting, unwearable suits for the first one or two iterations, and is a waste of your time and money."
All this, of course, takes longer and depends on you getting the alterations correct rather than having someone measure up and adjust accordingly. You still pay shipping to get the trial suit (and swatches) and return it.
However, if you know your measurements, then the KW route may be a good way to go.