Frog's gets knocked a bit because it's older and isn't the biggest gym in the world, but I'm a huge fan overall. It's small, but not too small. It's managed very well. There is never any shortage of scenery in there. But what is really great about Frog's are the many classes offered. I've become a big yoga buff lately, and Frog's has some great teachers and a lot of different classes to choose from. If you work in Solana Beach, make sure to get the corporate rate. Great location, very good management, and excellent FREE classes. And very safe too.
Pros : Safe, good location, good management, great classes
Cons : A bit pricey (unless you take advantage of classes), a bit cramped, older building