Which SIM unlock to buy?

[klymr]

I know it's been brought up numerous times everyday, but I don't want to spend the money on a SIM to not have it work if/when I upgrade the firmware. I have heard it said that some of the cards will stop working if you upgrade to 1.1.3. I have 1.1.2 on my iPhone right with the phone jailbroken.

Anyway, this guy at work told me to get a NextSIM because it doesn't require further programming to make it work. I've also heard from people that it's one of the cards that will stop working if you upgrade. People have mentioned the StealthSIM, but at $100 I'm still a little weary of buying it. Any suggestions would be much appreciated.

 

[klymr]

Anyone?

I found a Next SIM Pro (generation 5) on ebay with a starting bid of $1 USD. I'm a bit weary as the seller is in Germany and it also says on their page that it's $189 USD. They have a feedback score of 31 and it's all 100% positive feedback. Supposedly it will work with all generations of the firmware, including 1.1.3. I don't know what to do here.