Recyclers are best for whatever you like best. They are new to the industry being maybe 6-8 years old. They were basically made for concentrates but will work great with flower. They are smaller and will clog up sooner with gunk so a vaporizer like the Silver Surfer is amazing with a recycler. They add a little moisture to the hit, the cool the hit, and recyclers on average to not really go through a lot of water, but have a lot of bubbles to help cool the hit.
A larger piece is by most preferred for when smoking. At least a larger reservoir of water.