The Pit Boss is Timberland Pro's value 6-inch steel toe. It's been the warehouse-and-light-construction default for years because it lands under $130 and lasts a year for most guys. Leather upper, antifatigue insole, steel toe, slip-resistant rubber outsole. It's not waterproof in the strict sense — water-resistant is the right word.
The Boondock is the upgrade. Composite toe instead of steel (lighter, no thermal transfer in winter), genuine waterproof membrane, more aggressive lugged outsole, anti-fatigue technology in the midsole that's noticeably better than the Pit Boss insole. You're looking at $200-220 depending on the configuration.
Pick the Pit Boss if you're indoors most of the day, in a warehouse, on a flat shop floor, doing receiving or light assembly. Steel toe protects you from a pallet jack rolling onto your foot. You don't need waterproof. You don't need aggressive tread.
Pick the Boondock if you're outside, on dirt or concrete that gets wet, walking long distances on the job, or you're a framer/mason/utility who's standing on cold ground in February. The composite toe alone is worth the upgrade in a Northeast winter — steel pulls the heat right out of your foot.
We stock both at the shop. Try them on side by side. The Boondock weighs about the same as the Pit Boss despite the better build, which surprises most guys. See Timberland Pro for the rest of the lineup.