Alpen HPP Window Ratings
The Alpen Zenith Series is divided up into 5 different product lines, including the ZR-5 of 525, ZR-6 or 626, ZR-7 or 725, ZR-9 0r 925, and the ZR-10 or 1025 series. For instance, the "contractor" horizontal slider model of the Zenith 525 has a DP70, U-0.17, and VT of .43 and air infiltration of .07. Those are really really solid numbers for a builder grade product. In fact, many window manufacturers would like those numbers for their premium models.
The Tyrol series is divided up into the T6, T7, and T9 models. There is an optional upgrade to any of these called the PH+, which is a high end foam insulation on the main frame. The T6 tilt/turn model, for instance, delivers a .18 U-factor, .35 SHGC, .48 VT and a .03 AI. Impressive.