This is my first post on 2+2. I don't know anyone else who plays poker so I have no one to discuss this questionable spot. I've just gotten back into poker a week ago after a couple of years off. If I remember correctly my win rate was about 8bb/100 hands on pokerstars multi-tabling 10NL. I live in Australia so unfortunately I can't play there anymore. For the last week I have been studying like crazy and playing MTTs on Ignition. I think that if you can weather the variance there is a lot of money to be made there as the average player pool is incredibly soft. Just this week I have final tabled 3 times (twice in one day).
The hand I want to share came 3 handed at the final table of the SMPO event #54. $15 buy in with a $1.5 fee. 1,200 players.
prizes were (approx)
3rd - $1,200
2nd - $1,700
1st - $2,700

I know very little about ICM, but whats obvious is taking 2nd adds 33.3 BI's to my bankroll, and taking 1st will add 100 BI's to my bankroll.

In this hand I am in the big blind with 4.3M in chips. blinds are 100K/200K
Dealer folds (7.4M stack)
SB raises to 450K (6.7M stack)

I call with Q7h - pot is 930K

Flop comes 4d3h4s

V checks
I bet 250K
V calls - pot is 1.43M

At this point I assume V check/call range has a lot of Ax hands and medium pocket pairs. After further reflection I think that V would actually bet most of his medium pocket pairs and check/call the bigger ones. The could be some Kx suited hands. It's worth noting that I have a fairly aggressive image, not maniacal, but fairly high post flop agg.

Turn comes 5s
V checks
I bet 730K
V calls - pot is 2.89M

A larger bet size could be better to further polarize my range, but I wanted to make sure I had plenty of fold equity left for a river shove. I have picked up a gutshot. With the second check/call I expect there are still a lot of Ax suited hands, maybe Kx. Though I think any spade combo lower than Kx would have bet the flop, and if not, at least check/shove the turn. For some reason in the moment I still had the idea that V range included medium pocket pairs, though I now doubt how true that might be.
At this point I'm basically planning to shove almost any river card except an A.

River comes Qs

V checks
all of a sudden, my triple barrel bluff has turned into a potential value bet.
My first instinct was to check behind. But then, this idea that V range includes medium pocket pairs just kept nibbling at my brain. This was actually my 2nd final table in one day, so I was about 20 hrs deep into tourney play, my mind may not have been entirely crisp.
I figue V will find a hero call with 66-TT, which I guessed would have enough combo's to show me +EV vs all his hands that beat me 4x, Qx, pocket 3,4,5,Q,K,A.
I also though about how nice it would be to go heads up with a 2.1 chip advantage for 100 BI's. Maybe I got greedy. Maybe I was too tired. Maybe it was a good bet.
Anyway,

I shove 2.9M (potsize)
V calls, and shows Q10s.
I'm out in 3rd.

Are there any MTT experts out there? What would you do? Check or Bet?
I admit I could have made a smaller bet, not risking my whole stack. But as I've said I had those damn medium pocket pairs in my head and I wanted to polarize my range, trying to get a hero call out of those hands.

If you've made it this far, thanks for reading
There was actually another spot earlier in this final table where I folded 99 to a 3bet shove because of stack sizes and payjump considerations. That could be worth sharing also.
Happy +EV hunting
Peace

i usually go with my gut if i feel there's value to be had despite a scary board. however, villain is not going to check/call mid pairs on flop in this spot very often, so that plus the skewed ICM means i would avoid taking yourself to valuetown

when your starting out in poker, its hard to think more broad about the game you just have limited space in your head, after sometime this get more and more easy you will than have more space to think about additional lines and plays you can make.

So dont try to over complicate your game and take it day by day. And dont play more than 4 tables.

in terms of the MTTs try to have at least 300 buy ins minimum. unless its under 100 players than you can have 200 buy ins.

on the hand

your right a smaller bet on river probably would have been better you can bet 1/3 pot here.
I think vs your pot size bet its a chance he folds the 66-TT type hands. However I think he would not have those hands that often as he would not want to check call it on the flop, giving a free card so probaly he would either bet out on the flop or check raise.