i didnt try virgin sim, but have been looking for a good solution for a long time. Finally found the perfect sim for me.
working for 7 weeks now never needed a reboot

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Yessim SIM
calls, sms, data in/out: working
GPS: NOT working
Signal Loss: YES
Final Verdict: Fail

i-Smartphone SIM
calls, sms, data in/out: working
GPS: working
Signal Loss: YES
Final Verdict: Fail

iPhone-sim-unlock.com SIM
calls, sms, data in/out: working
GPS: working
Signal Loss: NO
Final Verdict: PASS - Working since 09/13/08