FLASH EVO DESIGN 4G TO STRAIGHT TALK (HELP PLEASE)

[tugmn5]

Can someone please help me flash/ root from sprint to straight talk? evo design has cdma/gsm sim. I no longer have sprint service. I have a straight talk phone with gsm sim. I have done some research and to my understanding I need to unlock it but I have seen too many dif ideas for doing this. If I unlock the nand does that unlock for service provider also? Maybe someone just has a link that they have successfully used. Also I noticed there is a wipe.. Do I need to back everything up from my phone, ie contacts and such? I want to be able to use my 3g on straight talk, my understanding is that I will not be able to use 4g when I do this. Are there any other negatives to flashing or rooting?Also would like to root so I can use my phone as a hot spot. Any help is appreciated and thanks in advance.