Like others, I think the 3D HD line is pretty good, and as custmsprty said, they have a complete line of cleaning products. As much as I like HD and use their stuff, I think I end up defaulting to Menzerna FG400/SF4000 for my basic 2-step polish. If I had the need to do an AIO, I'd use HD Speed and top with Proxy or Menz powerlock.
I think it's nice having one line up of products, but sometimes you need the benefit of having a bit of variety for situations that demand something different.
All the brands mentioned here (3D, Megs, Menzerna, BF, WG, etc.) all make great products and will serve you well for most of what you want to do, especially if it's just 4-7 cars, which which you are familiar (paint, drivers, conditions, etc.).
I keep two lines active: 3D & Menzerna.