SUPL vs gpsOneXTRA

im using ec25-eux and the question is:

for gpsOneXTRA do i need to use

http://xtrapath4.izatcloud.net/xtra3grcej.bin
or
http://xtrapath4.izatcloud.net/xtra3grc.bin

also second question is: i try to use this

AT+QGPSSUPLURL="supl.google.com:7276

how do i know that this is working and can process data ?

also are both gpsOneXTRA and SUPL ussed or we need to choose between 1 or another
so if i use ms-based or ms- assisted will gpsOneXTRA be used?

1 Stand-alone
2 MS-based
3 MS-assisted
4 Speed-optimal