I am not sure if they installed exterior stops on that job or not. I usually recommend the stops when space and the desired capping detail allows. If the unit is properly sealed to the interior stops, securely fastened to the jambs and insulating foam sealed prior to the capping then I don't see it as necessary for every application. The window isn't going anywhere. This could also be looked at as a good example of when less can be more. Too often carpenters use wood to fill gaps and voids in framing. Wood has an R-value of about R-1 per inch while the foam insulation has an R-6. Even in wood framed walls, the studs are the weakest link in the insulation of the shell. Modern framing techniques reduce excessive use of wood without compromising strength- i.e.: the use of header hangers to eliminate cripples & jack studs at window and door openings etc.
As for the grids on Schucos, because of the thickness of their sculptured grids, they only have them available on their double-panes and many people prefer the triple-panes with the flat grids and do not find them objectionable. As for the appearance of the windows, I like the clean details of the extrusions, the softer linen white finish and the steel lifts. Aesthetically, we all have different tastes. Hope I've answered your questions.