Tamron are known for their affordably priced, feature rich zoom lenses. The 17-50mm f/2.8 VC (Vibration Control) and 24-70mm f/2.8 VC are popular budget choice lenses for video shooters using APS-C and full frame cameras respectively. The latter a particularly interesting number as there is no other direct replacement for it (both Canon, Nikon and Sigma standard zoom lenses offer Image Stabilization or a fast f/2.8 aperture, not both).
Whilst Tamron has offered much in certain departments it has lacked in others. Build quality has always been a downside when comparing to other lenses, and short focus throws make them tough for video shooters. The new SP (Super Performance) prime pair look to make some changes, offering up a first for Tamron in the high quality fixed focal length sector (ignoring their current macro lenses).