Also a point to consider is how far away you are going to be when viewing the image, you tend to look at big images from further away. I have a print on my wall of a sunset, it was taken in JPEG and is blown up to around 17" tall and 55" wide, yes its pixelated but I continually get comments from people saying how fantastic it looks as they are always about 5' away from the print.
I also have a few orders to reprint it for a few of my friends.