Is this NELP3? I tested this and although I did get a connection, I could not measure it and therefor reverted to LPS. I read somewhere that if the reading is dBm85 (100%) with Network Signal Info, that the modem is not 100% compatible with the network it is used on. I don't have more info on this, but this is the reason why I discarded it as "tested but not suitable". All networks are not created equal and what works in the UK might not work as well over here.
As I am typing this, I am testing NELP3 again:
NELP3 gave me 4/6 bars of signal strength and a reading (100%)
Back to XXLPS:
XXLPS is giving me 6/6 bars signal strength and it registers dBm-79 (70%)
My conclusion is that LPS is better suited for SA, but you can use what you feel comfortable with and what works for you.