Speedo swimming goggles are of high quality, so they are best for swimming. I perfer wearing speedo swimming goggles because they are cheaper than other goggles and they are very comfortable to wear. They provide you with clear vision and there is no leaks. They have adjustable straps so that you can adjust the strap until they fit you properly, neither too loose nor too tight. But they may fog up slightly after you use them for a long time.
I think you can try speedo swimming goggles. I heard that the swimming athlete Phelps are wearing speedo swimming goggles when he attend Olympics in Beijing. So, i think it is worthy to try. And i also see some swimming coaches are recommended this swim goggles. Most of their swimming goggles are suit for long time swimming. With it, it will give you comfortable experiences to swim.