Game 1:
Underground game 2/5 - Average stack $750
10% rake up to $25 - $5 bad beat
I get $50 for first three hours of playing and $15 there after
15 minute drive

Game 2:
Casino Game
2/5 - $6 time charge
Average stack $1200
70 minute highway drive or $30 round trip by bus&uber combined

In terms of softness, the casino game would have mabye 2 more competent players per table. So game 1 has 2-3 solid players, game 2 has 4-5. I don't know if this matters that much as long as I have good position on the juicy players.

Which game is better? How do I convert the rake to time charge.

I don't at all understand the rake / promo at the underground game. They pay you $50 cash after 3 hours, and then $15 / hr in cash to play there? About how many hands per hour do they both run? Underground rake still seems "cruise ship crazy". If you win just two decent pots an hour on average your paying $50 / hr in rake! That's one hand per dealer at the casino, extremely low estimate. You could pay double that but I'll leave it this way for best case sunny day estimate. If they gift you back $15 your still paying $35 / hr vs $12 / hr at the time rake game.

Say you beat both games for 10BB / hr (and it's harder to beat the higher raked game for the same rate but since you say it's softer I'll let them equal out):
10 hr session Casino:
Total rake = $6 * 20 = $120
Gross profit = 10BB/hr * 10 hrs = 10*5*10 = $500
Transportation / time adjustment = -$30
Result: $350

10 hr session Underground:
Total rake = $50*10 - ($50 + (7*$15)) = $345 (at the minimum! and after your rake back promo gifts)
Gross profit = 10BB/hr * 10 hrs = 10*5*10 = $500
Transportation / time adjustment = 0
Result: $155

Yeah I negotiated a slightly better deal than other players. I think at this game a lot of others just pay the standard rake without the rakeback. Not too sure about hands per hour, but I would say that underground is likely 20-25% more hands per hour due to faster dealers.

How did you make the assumption that I would win 2 decent pots per hour on average? Do you have any data on this. Because if we change it to 1 decent pot per hour, suddenly the underground session becomes more profitable.

Makes sense with this structure they are making a killing and the greater amount of hands they deal the more they make.

I pulled it out of thin air. I've heard it used before in rake estimations and from personal experience it seems fair. At a casino the dealers typically change every 30 mins. How often is it that you dont pull a single decent pot from a dealer? Fairly rare, then again you could have one dealer where you win 3 big pots that would cover the next two dealers giving you absolutely nothing. Obviously you'll win some smaller pots too and at the underground game I suspect a limped heads up pot will even be raked for $1. And many hands will get a caller or two and be taken down on the flop (quick $6-10 rake hit).

The casino sure sounds better, unless you really hate driving and/or lots of really bad players really hate driving so the game is just way juicier.

So the proper way to do this is going to require some work. You need to get an idea how many hands/hr you are getting at each venue and what the average pot-size at each.

You already know how much is coming off the table at the casino, $108 or $120/hr (depending on 9 or 10-handed tables) Assuming normal game speed of 25-30 hands/hr, that means the rake there is between $3.60-$4.80 per hand.

At the underground game, it's hard to tell because we don't know how often rake hits max, but it is massive. Frankly, we hope it maxes often, as the massive pots where it becomes a smaller percentage of the total will be needed to beat this game. Pulling numbers out of the air, let's say an average pot is $150 at this game, so rake averages $15/hand. That means that an average $450 is coming off the table every hour, or $45-50 per player. Obv you need to do some record keeping to plug the actual number in here.

And remember that even though you are getting $15/hr in rakeback, the other players aren't, so that money is coming off the table and is not available for you to win.