For street leathers look into 2 piece.
One thing I've noticed over the years is that 2 piece is a little longer in the torso vs. a 1 piece.
Also, correct fit on a 1 piece is a nUt grabber when you stand up. 1 piece leathers are cut for on bike, sport position.
For street buy one size too big so you can put on long-johns, etc. For track you want skin-tight.
As Eric said get perf; front
and back for TX. If you get only front there is no place for the air to go out the back. My Dainese are only perf on the front and even at 150 there is not enough air flow in the summer.
I've had four set of full leathers over the years. My current Dainese are the best, and nicest by far. The leather is soft, the fit is outstanding, and the armor is simply first rate.
Check out MotoLiberty in SA. They have tons of leathers in stock and can help guide you to the right set for you.
Or...look into custom sets. The prices are really pretty reasonable.
Moto Liberty // #1 gear Store In Texas
For street riding I personally wear textile. I have two sets; Rev'It for the blazing heat, and a nice set of Buell Adventures for the rest of the year. I plan to buy a set of heavier Rev'Its for the cooler weather.