yeah, star, I don't know about the price and performance about Pentax lenses. I heard they used to be very good. since I have never used their systems, I have no clue anything about them. however, the re-sale price may suffer with P lenses. A friend of mine owns a Pentax 100-400 for Nikon (he is a D70 user). He paid $250 for that lens as used. I'd say it would be an unbelievable price, if it was a Canon lens. I tested his lens, it is not being so sharp as I would like to see. I think it may be a consumer grade lens? I may also have been too spoiled by my two 4Ls. lol
Nevertheless, this lens has, at least, a very professional looking. I'd say, it must be expensive.
