Great quality silicone, excellent dial for controlling vibrations. Nice and girthy too. It's waterproof and strong and it just takes two AA batteries. We don't use our vibes very often (she has a magic wand and a pure wand, that's why), so I've been concerned about buying the rechargeable toys. Two reasons: (1) tons of money for something that will never match the plug-in magic wand and (2) concern about internal battery issues if it sits for months without being charged. I know that this is an issue with the WeVibe II (if the battery is run completely dead then it will no longer accept a charge). I much prefer a couple of AA batteries (even rechargeable ones) and away you go! Of course, don't store toy with them in.
Anyways, after a test run with the Bet on Black, we'd say it's a great toy!