[RedJoker]

The cash game I play in my local casino allows an optional straddle aswell, but the straddler only has an option to check/bet if 5 or less players are playing.

How does this change the game? Well you're no longer playing 2/5, you're now playing 2/5/10. Automatically your stack is shorter because you're playing twice the limit.

Omaha is a flop game not a preflop game, by limping preflop you really are gambling that it's not raised after you. Position is crucial here and depending on the straddler it may not be wise to complete from small or big blind. Is he LAG or just a plain gambler?, how big is his stack?, will he pot it with any sort of hand if you limp in?

What are the advantages? Well if you get strong aces every hand and can commit most of your stack or someone else's heads-up preflop than it's an advantage. If you're naturally tight than having a straddle means you'll get better value for your big hands.

Disadvantages? Your stack is effectively halved, if you like to play a lot of flops than you need to add to your stack. If half or a quarter of the table are posting a straddle than it's usually the LAG and well stacked players who are doing it.

I think the main adjustment you must make is realizing you are now playing a short stack, and adjust your game accordingly. i.e. play much tighter.

If you are sufficently stacked and feel you can outplay most of the players at the table then the straddle really helps you, short stacks are under pressure and will make mistakes, post it yourself.