On the used market, I'd look for a Sekonic 308 if you just want a handheld meter like BradS is advocating - nice pocketable meter that does incident and reflected, ambient and flash metering, and gives you the readouts in easy-to-interpret Fstop-plus-graph readings with 1/10th stop precision. For a spotmeter, I'd suggest the Minolta Spotmeter M or F (depends on if you want flash metering as well (spotmeter F), or are concerned about battery availability (Spotmeter F takes an AA battery, the M takes a silver oxide battery). For a nice compromise, the Sekonic 408 has a 5 degree spot (the Minoltas are 1 degree), does ambient and flash, incident and reflected (dome up, dome down), and as a plus is weatherproof. I've owned all of the above mentioned meters, and have liked all of them (I still have the Spotmeter F and the Sekonic 408). In all cases, they're about half the price of the Pentax you're looking at. The 308 is still available new, in fact. It's a shame they killed off the 408, but I guess more people wanted the 1 degree spot metering on the higher end models like the 508.