I think Pro and Con boils down to the tuner available to you, the money you have available.. and which car.
Brand is totally irrelevant.. for example..if you drive Evo X..I think Cosworth ECPro is the best brand of standalone management available..but its totally useless in Malaysia cause nobody can tune it..unless you want to import the tuner as well.. lol. if you do that make sure you import Eric Hsu, I would like to meet him and shake his hand.