I have found
Jeyo Mobile Companion and am testing it our currently. It hasn't hung when I am downloading all the texts... And there is a threaded view you can do for individual people. The only issues I am having with it are:
1.) To edit the texts, such as moving them to folders or deleting them, the phone has to be attached as it is doing it live. I would much rather have everything done offline, and then when completed, it would resynch back to the phone.
2.) When looking at threaded view, I will try and change the colors of either my text or the person's text I am talking to, but this function does not work correctly and colorizes only parts.