I'm excited to be trading down...not trading necessarily, but I've sold my MR-G 7500 and have bought via Yahoo Japan Auctions a MR-G 3000.
It sounds pretty bad, but I found the 7500 a bit hard to use... Here are some opinions on both.
With the 3000, I get dual LED backlight and a bit easier module to navigate. I've heard the DLC coating isn't as good, but DLC is better than not. I have a GW-1600, so I know the size is good, and it feels hefty. The gunmetal color is really nice looking, especially with the blue face as contrast.
The 7500's DLC is incredible, and it is really light. Smaller than the MR-G 3000, which is good or bad depending. The lume is OK - better than other Casio's, but not in the league of a Seiko at all. The dark black of the watch is sharp, and the chronograph face is sharp.
So pro's and con's with each, but I think for me the MR-G 3000 is the better option. Let's hope it is!
Pics of each:
Link to the MR-G 3000 ended auction