I got a x301 since quite some time, and iam very happy with it! since the integrated ericsson f3507g is capable of doing AGPS (Assisted GPS, more info @ http://en.wikipedia.org/wiki/AGPS)
here are the steps which need to be done to enable AGPS
AT+CFUN=1
AT*E2GPSCTL=1,10,1
AT*E2GPSNPD
Now you can use gpsd to connect to your modem Device!
thanks to nikolai!
more info here:
http://www.thinkwiki.org/wiki/Ericsson_F3507g_Mobile_Broadband_Module