OK, I refrain from these contests because I'm no good at judging strength. Besides, I like reading what others think the strengths are. However, even before the final game was revealed as a pro game, I thought it was likely to be so. Look at how many moves are interesting. Look how each player uses the potential of the stones. How do I best explain what I'm seeing?
First off, I do not think there are many players above 8 kyu who are even aware that

at E2 can be a good approach. Once the players I know start experimenting with it, they generally do NOT use it as a probe. This move alone makes me think these players are at least KGS 1d, maybe 1-2k at the lowest, likely higher.
White's reduction starting at

further leads me to believe that these players are very strong. It's not just the position of the move (on the 5th line, slightly deeper into Black's moyo than I'd be comfortable with, but not close enough to the edge to be a typical invasion), but how it interacts with Black's weakness at L3 and with White's own aji in the Q5 and P6 stones.
The fight beginning at

and continuing on to the end of the game is incredible, at least once I took the time to really look at it. Up until Black's final mistake, both sides were handling this complex fight with strong, sharp moves. It feels like a very high-tension fight.
Since I'm writing this out, I might as well give some guesses, though I think my participation should not be counted, given I've read everyone else's posts first.

I'm just doing this for fun.
Game 1: 8k
Game 1 has some interesting aspects to it. First off, the players know at least a little bit of joseki, and maybe a small amount of fuseki theory. However, there's no feel of an overall plan from either player. The players have some idea of shape, but everything feels like a local fight, with no regard for the rest of the board. Of course, I could be completely off, and this could be a high-dan game where I'm completely lost as to the reasoning behind the moves, but I'll give my own go sense the benefit of the doubt.
Some examples of moves that make me think that the game is around this level:
1)

combined with

- First off, I don't know if

is actually joseki. The deviation might be playable, but when combined with

on the 4th line, it feels like the meaning of

is garbled a bit ... Black is playing too many 4th line moves, in my opinion, without having a solid plan.

on its own is a little suspect ... it's not really an enclosure with the R4 stone. Perhaps this player has played a number of games using
Sanrensei in their early Go career and is just starting to break into some 3-4 openings ... it feels like Black wants

to be like that. I don't like it.

2)

and

- White is making decent shape and trying to get the White stones to work together. Not a total beginner.
3)

- This move is fine, and shows some knowledge of joseki. I'm sure these players are at the point in their Go Path where they are experimenting with joseki and fuseki. On that note alone they could be as low as 11k. It remains to be seen how well they handle things after the opening is over and they have to deal with whatever shapes they've accumulated.
4)

,

,

,

,

- Makes me sure that these players are kyu level.

in particular is a move that is too small. I don't think I'd play it, and I don't know many players around my strength who would either. So, the range I'm considering from here is 6k to 11k.
5)

to

- The players are familiar with the monkey jump. This makes me sure they are not DDK, so I figure 8k is likely.
Game 2: 5d
Game 2 is a little harder to judge. However, there's more flow to this game. It feels stronger. Some of the moves really impress me, and the strategy and counting feels like it's a good deal above my own level. I'm particularly impressed by Black's willingness to lose the group at B11, and the two well-played ko fights back to back (I saw well played, but I also think the 2nd ko was slightly bad for White ... but I don't know any better plan at that stage of the game).
I don't think this is a pro game, though, particularly because of the 2nd ko. I can't point to anything else in the game that feels out of place, but that makes me think that maybe this is a 4d or 5d game ... the reading seems to be at the right level, particularly the exchange of

and

. I'll put this on the higher end and say 5d.
Game 3: 2k
Heh, this game made me laugh because of

... isn't this the wrong direction?

I know, attempting to go for a Mini Chinese opening, I think. White counters that idea with

... I like this. Up to

we can already see a good level of comfort in joseki shapes, and the running fight that begins next also shows good shape. Definitely stronger than game 1. However, at

it seems like Black is getting cute. There are a number of other responses that I would likely consider much better than the footsweep here, and it feels like Black gets punished for it. Of course, it then becomes a relatively big fight. All the while D17 sits there lonely ... not that it's bad, just that the fight has distracted the players from the largest open area of the board. I'd be confident in saying that this feels like something around my own skill level, and I think some of the flow of the game (particularly moves like

) is slightly above what is seen at the 4k level. Let's call it 2k.
So, to summarize:
Code: Select all
Game 1: 8k
Game 2: 5d
Game 3: 2k
Game 4: Pro
Please disqualify my entry for prizes. I peeked at other answers first. 