Denda... you still out there?

I'd like to know why you are considering them too - that really would help in the advice/stories we give.

I have aero-bars, but only on my TT bike (like Cat first describes)

My sons and partner all have aero bars too for their TT bikes.

My partner also has TT bars on one of his training bikes - this bike he uses for long distance training rides (on Sundays his training ride is at least 100km, but around this time of the year builds up to 150-160kms, so he likes the aero bars as a way to alter his position on the bike and give relief to his back, arms and wrists.

A friend who does tris has aerobars, but hers point up in the air - all of ours are parallel to the ground.

And saftey is paramount with aeros - like the others here have already said, never use them in a bunch ride unless you are on the front or at the back - you cannot break quickly, unless you have bar-end shifters you cannot change gear.
Your centre of gravity is altered and until you are really comfortable with that you can/will be unstable around corners and in cross winds, and when a vehicle passes you at speed, or a large vehicle passes you at all.

So get back to us - and give us the what/why/when of your aero bar wonderings