Our old PW1730 generator driving two PW1050s has a similar system
with a warning lamp. It is part of our monthly safety checks to
verify that no bulb = no HT.
I'd endorse the D5000 recommendation, though we've only had our twin
goniometer system (general powder and grazing angle options) for a
couple of months. The software is less intimidating to casual users
than the Philips equivalent to my mind. But I wouldn't object to a
X'pert MPD system if it was offered! A lot depends on your
applications, now and in the future. And on your funding!
---Graham Patterson http://www.rdg.ac.uk:80/~slspatte
Sedimentology: The hard study of soft rocks
*** Opinions expressed are mine unless otherwise stated ***