Personally I don't like them. If you are going to send rounds down range you might as well do so in a manner in which you can develop your shooting skills. I'll use a rest and a rear bag for initial sighting or running through a chronograph but other than that I'll be in a position such as prone.
I find them excellent for zeroing but thats bout it. It helps keep the gun in one position until shot is followed thru, so theres no question as to whether you moved or flinched and maybe thru your shot off. When shooting rounds that are in the $4-5 range a piece, Id like to zero in as little shots as possible. JMO
They will break shit if you load them up . The gun has to go some where and if it's tied down something has to give . Lighter caliber will most likely never show problems but if they kick it's for a reason bipod and rear bag will make you shoot better and done right it's better than a leadsled