I should have modified my post up there
Anyway, a special thank to adelmundo and few others that help me to adjust my mindset about this. I never heard of StraightTalk plan b4.
Can you provide some info about the plan?
I've tried to search but very confuse about what it is? Is it a AT&T pre-paid plan? or is it a company that using other phone provider services?
Straight Talk is an MVNO that provides prepaid mobile plans in the USA. They sell the phones and refill cards at Walmart and online and they use either AT&T, T-Mobile, and Sprint depending on what phone you purchase. Before you wanted to to get your unlocked phone on Straight Talk, you would have to buy a phone from them such as the Nokia N71, and take the SIM card and put it into your unlocked phone.
However a few months ago, Straight Talk introduced a Bring Your Own Device option where you could purchase a SIM card from them for $15 and then put it into your phone and pay $45/month for their unlimited everything plan.
Keep in mind though that although they advertise as Unlimited everything, there are some caveats to what "unlimited" really means. The voice and texting for the most part is unlimited, but there is no roaming I believe. Where the problem lies is the data part of unlimited. In their TOS, you are not allowed to stream music or video (like YouTube, Netflix, Pandora, etc.) Some people have been given warnings and have even had their SIM deactivated when they used to much data. On the safe side, some people have gone by the under 100 MB/day or 2 GB/month of data use to be safe. No one knows exactly what Straight Talk's criteria is or how they can determine if you're streaming or not. Most times they will give you a warning or 2 before they cut you off. If you look in howardforums.com, there are threads about Straight Talk, but as I have said, know one knows their exact criteria.
Most of the time I am on WIFI at work or at home, so I use very little 3G data. Their speeds are good if you do use 3G. You can even get HSPA+ (aka Faux G) if you have a phone capable of it. I had gotten on average ~2 Mbps down and as high as 8-9 Mbps in some areas.
If you bring your own phone that is GSM capable, you can use both phones that are AT&T or T-Mobile compatible. If you choose a phone that is T-Mobile compatible, you can request a T-Mo SIM. If you choose a phone uses AT&T bands, you can request the AT&T compatible SIM. You can even bring an iPhone on their network and can request the mini-SIM as well. I have also heard they treat the T-Mo phones differently as well, allowing them to use more data since T-Mo's data is unlimited, but throttled after 2GB. Although I don't know for sure since I'm not using the T-Mo SIM.
Straight Talk's website is straighttalk.com btw.