They're functionally the same, but in my opinion, the G05's have better build quality, particularly if you have one of the early rev deflection boards, which has a connector where every wire connects to the board, with strain relief. Much better than just soldering the wires directly to the board (which love to break off).
Electrohome cheapened the design with each rev, and pinched pennies by removing things that they deemed not necessary. I've been wanting to do an article about this, as I find it interesting. The G05-801 is the best b/w vector IMO, design-wise, and they just cheapened them with the 802's and v2000's, likely with Atari's input.
Overall they're all relatively good monitors, and can be made to run very reliably with the right work. But I've refurbed plenty of boards that have been abused, and the v2000 boards definitely hold up the least.