Best bong I ever used was made of a large piece of bamboo with a bamboo stem and a thimble for a bowl. They lasted about a year or so, then you made another. Unfortunately, I no longer have access to the bamboo. Other than that, glass all the way.
Small silicone bongs are great for parties and travel. Cheap. Don't break. Work. But otherwise they are usually not great bongs. They're surprisingly hard to clean. They're usually too small and often suffer from spray/backwash. I would spend a few quid on one to throw away at the end of a weekend (not very environment friendly) but a little glass bong almost certainly better, and probably not much more expensive.