B&H has the Pentax SMCP-FA 100-300mm f/4.7-5.8 for $99.95 (but apparently also for $149.95; what's up with that?) and the SMCP-FA J 75-300mm f/4.5-5.8 AL for $129.95. The Tamron AF 75-300mm f/4.0-5.6 LD Macro is also available at $129.
Has anyone had experience with these lenses? Should I try scouring the net for the Sigma 70-300mm f/4-5.6 DG Macro?