You can make a print as large as you want with digital if you do it right. Take your original image, in Photoshop, go to image, image size, then change the measurement at document size to percent, instead of inches in the size column it will read 100, change this to 110.
This increases the size 10% at a time, continue to do this until you get the size you want, there is very little loss this way. This takes some time, but it works well.
Personally, I change the resolution to what I want prior to starting the increase. I typically use a resolution of 125. I know this seems low, however, we have a Mamaki 60" wide format printer, (which actually has Epson printer head) the software actually increases the resolution of the image when it goes to print. Using 300 res files seems to produce a lot of bleeding in the final image, it also takes forever to rip.
I don't don't know how this works with other Epson large format printers, this procedure works best for ours. I make a lot of 48" and 60" prints this way.
There's my two cents worth.