I'm a PENTAX lover/PENTAX only guy too. And my K-1000 will ALWAYS be with me. The light meter is not bad in the K, but some new ones have the ability to do pinpoint and multi segment light readings for high contrast situations where a regular meter will be confused. Newer models can also do auto-bracket, where it will take 3 different exposures: One at the metered exposure, one under and one over. You can program them to be 1/2 or a full 1 EV difference. So yes, they are much better in difficult light situations. Not just the meter but the whole package itself.
The ZX-L seems to be an excellent choice. I'm waiting for the *ist to be available so I can check it out. It seems like a good candidate for my next camera. The only feature I really want beyond my K-1000 is multiple exposure in a single frame.
Thanks,
Ismael