As Dave mentioned earlier, that is a very broad question. Food for thought.. Many Pool Builders are given special incentives, better customer service (repair, replacement parts, etc.) if they carry a specific manufacturers brand. Some of those that come to mind... Pentair, Jandy, Hayward are just a few.
If you are a DIY'er and plan to build your own pool, then you will need to do your due dilligence in coming up with a setup that you feel is the best bang for your buck. That may include using a specific piece from each manufacturer or you may choose one manufacturer for your entire setup.
My PB's main line is Jandy and Hayward products. Obviuosly those are the main components in my current setup. Are they efficient. Based on discussions I have had with other pool owners about electricity usage/ turn-over rate on pool, yes my equipment is efficient. I have had no problems with any of my equipment to date (Pool= 1 year old this month).
Again, as mentioned earlier, this is a broad question and I think loads of people can chime in and tell you that the equipment they have is part of the package that their pool builder suggested. I wish you luck in determining your setup.