I've never used a 1084, but I can say my PVM-14M4U produces an excellent picture. I do have an interference problem with some of the things I hook up to it, but it might be due to low-quality cabling.
One thing I've noticed about my PVM, though, is that the vertical linearity is somewhat off. I'm sure there's an adjustment for it (I mean, there is on my TV, and this is a much more precision piece of equipment than my TV), but I haven't looked for it yet.
EDIT: When I say the linearity is off, I mean just slightly. I don't notice it on static images, just when things are scrolling vertically, as it makes it look like things moving through the top of the screen are moving faster than things moving through the bottom of the screen.