First off, it has excellent build quality, in-line with all of the DA* lenses, smooth rotating barrels with the perfect dampening feel, accurate and swift AF (I find the AF start to finish from near to infinity quick and responsive, much faster than the DA*300) and a useful tripod collar when the weight begins to bear down.
The gem about this lens, is its functional zoom focal length, perfect for outdoor sports, and for me it gives me more flexibility when shooting surfing from an elevated vantage point, such as a pier.
Being a telephoto zoom allows you to really take advantage of "compression"...
"Modern meets Classic"
Comparison of focal length extremes
AF tracking, and action photos to follow...