Hey man, most DOPs ive worked with use sekonic, ambiant and spot functions - these have been mentioned by others and thats not why I messaging you,
a dop friend of mine in sydney once told me many of the best dops carry 2 meters, and valways spare batts. as you can imagine if one meter screws up there is hell to pay if you dont notice so its all good to compare readings regulaly.
also buying lx meters on ebay saves a lot. but if they are abroad get them to write 'in for repare' as tax issues arrise.
good luck mate
j