If you love a clean, minimal look, the COR 70 Hidden Sash is worth a closer look.
The opening sash hides behind the outer frame, so from outside the window looks like a single pane of glass.
Concealed hinges, an optional invisible handle and hidden drainage keep the lines clean, and it’s available as tilt and turn as well as side hung.
It’s PAS24 certified too, so you don’t have to choose between style and security.