For the GTAW process, we use 309LMo. Our WPS is limited to the Avesta product (the Cr and Ni content was out of spec with SFA 5.9).
For FCAW we use 309LMo T1-4 (again, Avesta).
I'm not making any claims about the compartive status of these filler metals with others; just letting you know what we use.
Charles