Originally Posted by FlyingDutchman
Cons: gets in the way.
Pros: makes it easier to stand up while casting or spotting.
If you have a good floor and are smooth with the oars, you don't really need a thigh bar. If you are taking older fisherman/woman a thigh bar is a good thing.
That's pretty much the jist of it.
I will add that I've never been a fan of them in rafts. I do like them in hard boats, but even some of them work better sitting down (SF Skiff for instance). I've always maintained that they get in the way and are useless in rafts, but I've been rethinking that abit, due to my 75 year old father. He gets frustrated because he knows what he wants to do, where he wants to cast, but is frankly too slow to make it happen most of the time. I'm planning on setting something up for him this year to see how he does, but I fear that standing will only add to the difficulties for him. I could see the casting brace going either way. It'll put him higher with better vision (standing vs sitting) but he'll have to worry about balance, something that is rapidly disappearing for him.
For those of us with more of our original agility, fishing from a high seat in front of the raft is far superior to me than standing. I have mine set up so that your front feet rest on the bow and you can very quickly spin and adjust to hit various features and in reality I'm usually sitting at some angle with one foot on the rubber and one on the deck. Another advantage is if (when) you get fly line under your feet you can just pick one or even both up and get it undone without really loosing your balance. Really one of the biggest issues with standing and casting is standing on your fly line. I've tried stripping baskets, but for me, I'm rarely facing forward and the line still ends up on the floor AND tangled around something on the brace/basket.
The rear seat is the one that I can see benefiting the most. I've got mine raised 2 inches off the seat mount which really helps but it definitely lacks vision. That's where I may put my dad and casting brace this summer as I already have a nice hard deck back there and he'll have more room. But only time will tell.