Depends what your main uses and other components are.
If you're gaming and using a graphics card stronger than a 5870, go i5. If your using a 5870 (or 5830/5770 crossfire) or worse, go for Phenom II 955 (unless you are using a 30" monitor or eyefinity on a super high resolution, this will cause more stress on the GPUs, allowing OCed Phenom II to be enough for even 5870 crossfire and more).
If you're using CPU intensive apps that can use more than 4 cores, or you are doing some massive multi-tasking, go for the 1055T. For encoding or CPU intensive tasks that don't use more than 4 cores go for the i5-750.
This is still a vague answer for a vague question, however.