I lined up the HGUC Jegan I recently built and the MG Jegan I built a while ago.

Both were painted with a brush; the HGUC was painted in a lighter green, similar to the color on the package, while the MG was painted in a slightly darker green.

Looking at them side-by-side, the HGUC seems to have a more robust style, while the MG looks sleeker. (I like both, though.)
Now that I think about it, the MG took longer to build because the parts were more finely divided, but I remember it was easier to paint.

So, while the HGUC Jegan was easy to build, the MG Jegan was also quick to build.

HGUC Jegan and MG Jegan | halsonic's Gunpla works