Just a note - the 18-35 lens arrived from Teds, in the original Pentax box, with manuals and paperwork. But no lens hood was supplied, nor was there a front or rear lens cap in the box.
Plus (unsurprisingly) the front and rear lens elements were dirty
In other words, this isn't a new and unused lens. Perhaps an ex demo item or a return. If you buy anything from Ted's on clearance in future, be aware of this.
However in my brief tests around the house the lens seems OK optically and seems a keeper - no scratches or marks, no obvious decentering, no visible CA, reasonably sharp when stopped down a notch. It seems to perform better at 18mm than other focal lengths, but that's OK. Plus it is incredibly light and compact for a wide-angle.