To Use Synthetic or Not to Use Synthetic . . .

I just did my first oil change on my 00 2.7L Trep and I used Valvoline Synthetic. I am not sure whether it is my driving habits or what, but I have seen an increase of about 5 MPG since the oil change. I have only had the car 3 months so its hard to say if it is worth it. I quess I will find out over the course of the next year or so.

I failed to mention that I purchased the car used. It had almost 31,000 miles on it. I changed the erl at 34,000.