I agree with Jim. I say this as someone with a drum scanner, a proponent of using the right tools for the job, and someone who will by instinct try to convince you to go with a drum scan because, let's face t, I sell that service and have a stake in it's superiority.
On the other hand I have worked with a lot of color neg scans from v700s/v750s, carried out meticulously, and the files carefully worked for final large print size from 120 and 4x5, for example this show-
http://www.custom-digital.com/2011/0...r-photography/
these prints were not quite as large as yours, but we have printed some of the same files larger, and your film is larger to begin with.

I'd liked to have drum scanned her work, side by side a discriminating eye may find a difference, but on their own they are stunning prints with no impression of anything lacking. Proper technique, and in particular, careful sharpening practices are critical. I'd add that a higher density film, like transparency film, with higher sharpness and resolved detail, and lower grain, would have revealed greater differences between the scanning technologies. With color neg scanning we are usually trying to keep grain from overresolving, more like an enlarger might depict it. It also depends on the image content.
There's no harm in giving it a try.

Tyler