Borrowed from a write-up I did for PTN, obviously added a bit to fit NESPlayer's format.

Graphics: 5/5
Sound: 4/5
Control: 5/5
Frustration: 2/5
Fun Factor: 5/5
Overall: 4.5/5
This game gets a lot of flack for being unoriginal and outside of the genius that is the NES Mega Man series. It introduces Mr. X (yawn), so they at least tried to change it up. But really, given the technical limitations of the system, they couldn't do anything too new anyway.
Point being, for those of you who have never played it and only read smack on it, give it a shot. It's really a lot of fun. It's the first Mega Man game I ever picked up and I played it before reading any bs about it. I loved it. I'm glad I didn't have the opportunity to sheep my way into hating it.
Speaking of new stuff, what really cracks me up is the boss-breakdown scene. It gives you the bosses stuff. I know we've all thought, "sure, Hard Man is hard, but how heavy is he?"
The action is typical NES Mega Man game play, which, needless to say, is aw3some. You shoot robots, platform, and just generally flip out and go crazy. True to Mega Man 4 and 5, you can slide and charge your shot.
What really makes the game can be summed up in two to four words, depending on how you group them (I use 2): muthaf**k'n jetpack. Rush, instead of being a dog, is now a suit, and that dogsuit never looked better. The jetpack doesn't use weapon ammo like standard Rush functions, instead it's rechargeable, so you get a lot of game play out of it. You have your arm cannon equipped with the jetpack, but you can't charge the shot (I'm guessing it would ignite the jet fuel).
Storyline: Mega Man has to go kill a bunch more robots.
Gameplay: Really fun, and obviously tried and true. I think this one really one-ups the previous installments with the additional suits you can use, especially the jetpack. BEAT, for as much shit as it gets, is actually very very useful in the right situations. It's quite a bit like an allen wrench--you never use 'em but when you need it nothing else works quite the same. Not the greatest powerup in the world, but a lot of fun. The 8 Robot Master levels are a bit short, but good--though the game really opens up after that. Those later levels are the ones that really make the game worth playing.
Sound/Music: Same sound fx, different music. The sound track is definitely not the most inspired of the Mega Man series, but I'd still say it's better than average.
Graphics: The game looks freaking great. It's real polished. It's got a great color palate and the enemies even hide behind the background and stuff. Some of the best on the NES, I'd say.
Nostalgia Value: Most of us probably won't remember this fondly from childhood, as it was released well after the SNES and never sold too well. This one was likely only picked up by the Mega Man die-hards and the kids who won the Nintendo Power contest (see below).
Bottom Line: As a stand-alone, this is a really sweet title. Don't listen to the BS this game gets. Like Castlevania II, it's very undeserved. I'd pick this one up. For the gamers, it's a really fun title. For the collectors, it's a great late-release that is continually appreciating in value. I bought this 3 or 4 years ago, in great shape, CIB, for $14. I've played it through several times and I've seen comparable copies sell for $60. I've gotten a lot of gaming and collectible wonderfulness from it


The box art is pretty sweet too. To exploit the aw3someness, they naturally depict the jetpack. I'd say it's the only NES Mega Man game whose box art isn't terrible.

It's also worth noting that Mega Man 6 is linked to a Nintendo Power promotion. The promotion was letting two Nintendo Power subscribers design and name one of the bosses in the game. Knight Man was designed by Daniel Vallie (Canada) and Wind Man was designed by Michael Leader (United States). (Rumor has it that Capcom wanted to stop the NES Mega Man series at 5, as they wanted to focus their efforts on other products. However, because of this contest, they had to release it. So, it was released in a very limited quantity, making the game somewhat scarce today. To help Capcom, Nintendo released and distributed Mega Man 6 to allow the team to focus on Mega Man X for the SNES. This makes it a rare third-party game licensed to Nintendo [not the other way around].)
Links of interest:
Wiki:
http://en.wikipedia.org/wiki/Mega_Man_6NA Mega Man 6 portal (inc. box and manual scans):
http://www.nintendoage.com/index.cfm?alpha=&Keywords=mega+man+6&FuseAction=Search.Results&Search=simpleMega Man 6 password generator:
http://www.mmhp.net/Passwords/MM6/
Recommended Order:
Plant Man
Wind Man
Flame Man
Tomahawk Man
Yamato Man
Knight Man
Centaur Man
Blizzard Man