Well, I've gotten through my fair share of playing. Time to vote!
I've played all of the Match stages as well as the Single Player stages three times each. The games were almost always played in Software mode and as Sonic. I've considered scores on each playthrough, being sure not to pull any punches, and this is what I've concluded:
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MATCH CONTEST MAPS
MAP01 - Greenery Hills 2 - JJames19119
SCORE: 6/10
This map is pretty streamlined! The action was pretty well paced and thus I had fun here. The flaws aren't numerous, really, but they hurt. A: Automatic and Rail - This is too powerful a weapon ring combination. I'd get hammered by that half the time. B: Too cramped. I always felt I had little space to move. If the land mass was a bit bigger, this wouldn't have been a problem. Still, I liked this map.
MAP02 - Cynicism - RedFox34
SCORE: 6/10
As much as this map is small, it's also pretty sharp. The symmetry and the simple layout don't leave you guessing about the level, but rather actually focusing on the action. I don't have much to say, except the use of random monitors kinda' makes matches a bit catastrophic (especially when you draw an Attraction shield), and the size hurts a little. Sharp, though.
MAP03 - Insanity Planet - SRB2-Playah
SCORE: 4/10
Insanity Planet is insane! The effects were nice and all, but the gameplay was pretty abysmal. The main problem with this map is that its area-to-ring ratio is way out of place - the field was way too big for the ring count. Way too few rings. I also felt that the weapon rings were a chore to grab.
MAP04 - Amphitheatre - Oogaland
SCORE: 6/10
This map is pretty cool. Mechanically, it works, but there are a few big-hitting flaws to it. A: Ring Placement - The rings in each row are a bit too spaced out, thus making it slightly harder to grab a good lot. B: Level Design - It's all too broken up. On the bottom, it's all flowy and speedy (which I liked about the map), but once you try going up the seats, it becomes a chore to move. Fortunately, I didn't have to do that too often, so I had fun with this map.
MAP05 - Peach's Castle - Chaos Zero 64
SCORE: 3/10
While a cool concept, Peach's Castle doesn't really do a lot of justice as a Match map. You've got all these super-powerful monitor power-ups to let players cause chaos among the map, and the rings were rare. As Mystic said, I wanted to love this map, but I didn't. At least it was a pretty decorated map.
Btw, the NiGHTS thing is cool and all, but I wasn't really impressed. Working on BSZ kinda' takes the fun out of NiGHTS gameplay... at least for me.
MAP06 - Diving Meadows - Sonicandtails218
SCORE: 4/10
The layout is way too complicated and cramped here. It's rare I even encountered another player so I did more running around than fighting. When I did find someone, the rings would be obstructed by the obstacle-esque structures. The map was pretty explorable, though.
MAP07 - Up and Down - Sonicandtails218
SCORE: 4/10
Although the layout was much simpler, same thing applies here as last map: I didn't really score any points, and all I did was run. This is really attributed to Sonic, as you have some real running space here. I didn't like how the rings way up top weren't within walking height. Oh well.
MAP08 - Koth - Hotdog003 & Spazz
SCORE: 3/10
In its own gametype, it's a pretty alright map. However, as a Match map, it fails. You have a limited amount of rings to shoot and once you run out, you're forced to kill yourself and lose fifty points, or have someone kill you and have them gain fifty points. It doesn't really do a lot for the fairness. The amount of rings granted to you as well is pretty slim.
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SINGLE PLAYER CONTEST MAPS
Wed - Arf
SCORE: 3/10
I'm sorry, but as much as this map has some cool features, it's outshadowed by poor design. The hallways are too cramped, only one starpost works (which, btw, isn't very good), and I forced myself to walk slowly in a few areas. I haven't completed the map yet.
The good thing about this map is that it has a notable replay value. The level actually inspired me to try the different paths.
Dark Palisades Zone - Tets
SCORE: 8/10
This map is ace. It had an amazing amount of flow and it fit for all three characters. Although I felt the design was a bit too advantageous for Tails, as Sonic I had a lot of fun running through. If anything, I felt the map was just a tad bit bare, but that's only to a very small degree. It was outruled by the cool features of this map - I especially liked the ending after the waterfall.
Aerial Factory Zone - Sonicandtails218
SCORE: 4/10
The beginning sequence of the stage, while not really seen a lot, was pretty pointless. I wasn't 'wow'ed by it too much, but I think that was the best part of the level.
As for the level itself, it didn't wow me either. It's too simple and too short. An obstacle course using lasers and conveyor belts doesn't really excite me, as it's not fast paced. I also ended up killing myself with the bottomless pit towards the end; that was pretty cheap.
Storm Ruins Zone - FuriousFox
SCORE: 7/10
Not bad! It was either slightly linear or the forking of paths was really obvious, but the level gameplay itself made up for that. The flow here is pretty nice, especially as Sonic. The main problem here is that the map's too bare. Perhaps it is that you didn't have enough time, but the hallways were a bit boring. It would've made a bit of difference if you even placed a few more Crawlas here and there. It's not a bad stage, though.
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This contest's entries... well, the Match entries were average at best. I apologize, but I wasn't too impressed by the overall result. The Single Player entries were alright, though.