I liked it a fair amount.
Its not like this was made and the author tried to make good graphics but they turned out bad. The game was made with these graphics because it was the author's choice to have them.
In case no one knows, the Windows 98 achievement apparently is just changing the quality of the game, but as you might notice there really isn't a thing on there for quality :(.
Other than that quality thing, this is a good game :D.