A heavy, meat cleaver is for heavy, meat work ONLY. It is NOT a "Chinese chopper" even though it looks somewhat the same from the profile. It's the completely wrong choice for doing things like prepping vegetables, portioning bone-out meat, etc., and even used carefully it's weight will end up destroying your board. It will not "enhance" your prep in any way, shape or form.
They make nice wall decorations though.
The appropriate bevel depends on the particular knife. Many older cleavers have been so over-used and over-sharpened that the only possible bevels -- without serious re-profiling (i.e., thinning) -- are quite obtuse.
I have an old Chicago Cutlery carbon-steel meat cleaver, made in the sixties, which is in pretty good shape. It's sharpened to a 22.5/15 double bevel, and although it's usable it never gets used because I have several knives which do the same things but do them better, with less effort, and require less maintenance afterward.
If you decide to try using a meat cleaver to hack through bone or whatever -- put it where you want it to cut and lean on it. Even, if you must, give the spine a rap or two with a rubber mallet. If you feel an intense emotional need to take a whack at something -- say a venison rib cage -- do it with very controlled force. Once you're started through the bone, you can usually rock the cleaver the rest of the way through.
Don't swing it like an axe or you'll wreck your board with one whack.
If you want to try the type of "cleaver" Chinese cooks use for general prep get a CCK (if you can live with carbon and its vicissitudes) or a Dexter-Russel Green River.
If you go through a lot of heavy bones as part of your ordinary cooking, get a saw. The kind of rechargeable battery powered reciprocating saws handy men use work better than old fashioned meat saws. If you split chickens all day long, get some (inexpensive) heavy-duty, spring loaded shears from the hardware store.