Acoustically, they sound nearly the same.
On Martin guitars, this is a really big deal.
Serial Number 20079 would Indicate Circa 1868 to 1869? Fancy backstripe, ebony fingerboard, hexagonal abalone fingerboard markers from 3rd to 15th fret, triple bound peghead, vertical pearl logo, volute on neck.
This will greatly influence value.
Vega arch top acoustic guitar in excellent condition.
My guess from looking at lots of photos of Vega mandolins, banjos, and mandolin banjos is that the word 'Vega' was not engraved in the stars until the late 1920s.
Only about a dozen were made.
These late-1938 to late-1944 guitars had deeper scalloped braces than the 1938 and prior forward or advanced braced guitars.