There isn't really a "best". At this point, each tier of price/quality has multiple options. When we do a lighting design, we use a mix of manufacturers because mfr X has the transformers we like mfr Y has killer pathlights, mfr Z does great bullet lights, etc. If you're doing the install yourself, I would suggest working with a supplier who offers several lines who can advise you on what's best for each application. If you're having a pro install it, they should have a bunch of manufacturers they pull from depending on the purpose of that fixture.

Agree with Revolutionary Gardens--some of the brands we offer for landscape lighting include Kichler, Hinkley and WAC. All of these brands have stylish, high-quality lights for many different landscape applications.