At 730g front, 920g rear the Streamlines are lighter than most mid-priced wheels, which will put some spice into the acceleration and agility of your bike.
The 27mm-deep rims will cut through the wind slightly better than shallower, flat-faced hoops too. However, the real reason that most people are going to grab these wheels instead of others are the spokes. The white-painted, flat-bladed Sandvik spokes look top dollar compared to the mass of black wheels available.
Despite being laced radially on the front and offside (which can create loosening problems in less well-made wheels) we’ve not had to take a spoke key to them all season. The adjustable cartridge bearings seem equally unconcerned with winter abuse.