I would like to use a 3xFLAG fusion vector in which I will insert my specific protein. I currently have the type of vector I require narrowed down to two. The difference between these two vectors is whether 3xFLAG is on the C-terminal versus N-terminal side of the protein. Does it matter which terminal the 3xFLAG is located? If it does matter, what criteria do I need to take into consideration when determining which vector to us?