Is there an inherent advantage/disadvantage to having a larger stack than your opponent in a cash game? I know it can affect tournament play. I would think if you expect to have a skill advantage over the table, you would want your stack to be as big as the biggest stack at the table so you can maximize your potential winnings. However, going into a random cash game where you don't know any of the players, would it be wise to buy in at half the max buyin so your maximum potential loss is smaller?
No. There is no advantage nor disadvantage, because you play for his stack, not yours. If you have 75 BBs and he has 40 BBs, the maximum you can win is 40 BBs, the rest of 35 BBs being returned to you.
Here, there is a longer discussion and, by the way you ask the question, I suspect that you have a much stronger background in tournament play than in cash games.
As you might know, in cash games, the blinds never increase. As you might know as well, in cash games you can buy in for any amount which is between two fixed amounts, set by the casino. However, in cash games the pots grow almost geometrically, so it's not very hard to go all-in by the river, if you really want it to. As an example, if you raise preflop to 3 BBs, you get a caller and on each street you bet the pot, after the river betting occurs, you would have invested 107 BBs from your stack into the pot.
The implications of what I said earlier are these: if you have a short stack (40 BBs), then, because the pot grows geometrically, it will be very easy to go all in. In the worse case you'll go all-in on the turn, because you have little money to play. This means that you are forced to play big hands, because you need to win now. There is even a known, mechanical strategy, called short stack strategy, designed to play if you have little money behind. Although it's mechanical and you cannot make big mistakes, it's not a huge money maker. The difference between high and low cards, difference known as the gap principle is huge. If you play speculative hands, you will not win enough to compensate for the frequent losses due to the fact that you missed.
If you buy full stack (100 BBs), you'll have more money to play, it will be harder to go all-in, so you don't need all the time to have big cards. You can also play speculative hands that can form a monster hand and win the opponent's entire stack. Here, you can risk 3 BBs here, 3 BBs there because, in the most cases you'll miss, you would have risked 3% of your stack. The gap between high and low cards is lower than in the short stack scenario. If you hit and stack off your 100BBs opponents, it's more than enough to show a profit.
If you buy deep stack (100+ BBs), then the game is much more skewed towards speculative hand play. The gap here is so low, that you will almost never see AA or KK going all-in post flop, unimproved. Because you have so much money behind, on the long term it pays off waiting for a big hand (full house or quads) and shipping the money into the middle.
As the stacks increase, you need to me more skilled at play to be profitable in the long run. Anybody can shove KK being short stacked, but not anybody can maneuver his 250 BBs opponent into shoving his full house into the hero's quads.
The amount you buy-in going at a random cash game should reflect, IMHO, the skills and confidence that you have. If you want to test the waters, buy in short stacked and play mechanically. However, if you trust in your game, buy in the maximum allowed at that game. Don't think about the potential loss, think about the potential gain that you can have. If you are as good as Phil Ivey, you wouldn't think twice in going into a table full of unknown players and buying in for the max amount.
To answer your initial question, my opinion is that yes, it's more advantageous buying in for the max, because you can win as much as you can.
I hope it helped.
I agree with Gaz above in that having a big stack means you can get paid more for you big hands. Also, as Gaz points out, if you have a big stack people have to think about potentially facing more bets on later streets. This can be an extra encouragement for them to fold. So I do think that a big stack plays better.
I have however seen some players buy in for smaller amounts as way to reduce risk. Since they do not have a lot of chips at the table they do not have to worry about those bets on later streets. The number of chips they can bet (and therefore lose) is limited. If they lose all their chips they just buy in again for a small amount. Low risk. On the flip side they cannot get paid big for their big hands.
So I guess it is up to you. Do you want to win big or avoid losing big?
I agree with the two responses above, but just want to point out that your style of play also needs to be taken into consideration. Some players are better at short stack play and prefer to play from behind, so to speak. Other players like the ability to bully and push people all-in.
I think you're style of play should have some impact on your buy in amount.
It really depends on the other stack sizes at the table. If you buy in for the minimum and everyone else at the table is lower then its fine. If there are people with max buyins then you need to buy in at that.
You want to be able to maximise your profits and you are not able to do that if you can only take half of an opponents stack.
Also by having the biggest stack at the table it puts a lot more pressure on people when you make big raises. Which can lead to them calling a lot wider and chasing draws more which gets you more profit when they miss.
So I would say you should always buy in at the max. Most pro's would tell you the same thing.