I’ve had a Helix for about three years. I was looking for a good piece that was easy to clean, and this has far exceeded my expectations. The slider that it comes with is small, but enough for a decent-sized hit for one person. The spiraling of the smoke really works well to deliver a smooth hit (pack loose and draw slowly or it will hurt you), but the wider bowl available also works great. Cleaning is also easy, just a piece of cloth and cleaning solution are enough to keep it looking new quite easily.
The pieces are pretty sturdy, but I’ve lost a small number to accidents (which they survived most of).