So I thought I'd put it here and link it from there.

This game is simple. There are no skill trees, no personal stats, no one level slope.
I do mean no ONE level slope. You don't get to see your character in level 60 and then slog on untill level 200.
What you see, though, is many, many weapons, all with the level cap of 10.
And each weapon has their own kind of secondary attack. So that's skill and grinding covered.

Now let's take a moment to talk about the experience.

This game is home to a great big monster called Overseas Connection Lag. i.e. all your actions are postponed by a second or two in the actual records. The things you kill (monsters) will behave a little oddly when hit, and when things gets harder you'll find YOU are the odd one. In fact, if you see videos of runs in this game everywhere you'll find that they play more normally.
This is okay for most things, but a few more action-demanding monsters throw more things at you with no regard of wether you shot first or not. There are many things I have felt frustrated on how many monsters are horribly quick in attacking, but then OOO (developers of Spiral Knights) isn't able to make them easier or slow them down, because that will lose its intended behaviour to players who can actually play this game with a good latency.

It's a great note that Spiral Knights reward (or for some cases, requires) split-second reflexes. But there will be many times where your split-second shielding or dodging is betrayed by server priority (e.g. monsters being able to hit you after you have shielded). It's another great note that it does that to prevent client hacking, but it's not very forgiving to players with weak connection.
And it shows. If you were to disconnect in the middle of a frozen-in-time battle, you're better off waiting for a few good minutes before reconnecting. You can try to reconnect immediately and hope to be back in battle, but chances are you'll show up dead.

No lag differentiation/prediction features exist in the game. And there are currently no plans for expansion of servers, so don't get your hopes high.

And if anything, a real complaint, I'd say the general directional aiming could use some work.

SO(!), if you're from the US or UK, great! This game is a really great game, and you should play it. Heck, if you like MMOs or at any point of time you are thinking "what I need now is an MMO", PLEASE try this out already. If you're the sort that loves to grind 24-hour shifts, you'll need some planning and... other games (take up a hobby!) because of the energy system. But that's what the energy system trying to undo: The graveyard-shift grinding.
Some players may argue that there's a travel pass to circumvent that, but the game's level generator has its variety limited just so that you will feel sick of playing many, many areas of differently-assembled-same in one sitting, but still makes room for exploration every level you enter.

If you're from anywhere else that gives one red dot on the top right screen in game (that's supposed to be a connection bar a-la your phone's reception, by the way), still, give this game a try. Spiral Knights has a great beginner crash course (there wasn't one last time, so it got better). If you really like this game, you can keep playing from there, but be warned that further down the tiers (area progression difficulty) you'll find that the game gets ridiculously hard to cope because of lag and the like.
You can't blame anyone for that, but don't blame yourself. I had to endure 400+ hours of that, so take my word for it.

Personally, I contributed 50+ USD to this game. I do not regret spending that amount of money, because I believe all that bit will help OOO make more games and better up Spiral Knights.
I had a lot of fun in what is essentially an Arcade, and I made friends with the same predicament as I have. However, I don't see the point of playing the game at the condition it's not meant to be.
I used to think of it as an extra challenge to play with the latency. But then even with all the extra things I do differently from the rest, I realised all that energy would be better spent on tackling the shadow lairs (the End-Game-Difficulty-Plus-One mode). There is just so many times you can targe and charge, then realise the others don't have to.

If I enjoyed anything as much as everyone in this game, even those with a good connection, it's spending my mist energy (daily rationed energy) on making 2-star weapons and selling them. It's those easy little mundane things that keeps me going. I spend 70% of the round time in Red Alert making hundereds of one thing to finish off the last unit, and went all Sim City on C&C Generals.
Games need little for allowance of some little distractions (in other words, break the monotony). Spiral Knights has this at the very least, and I'm happy with it.

In short: Play this game. If connection is bad, I recommend you don't take this game so seriously or competitively.