After the total disaster of the first Osmo Action we got that just stopped working we now have two of them in the family one for me and one for Annika and so far we are very happy with them - acessorywise we have one charging dock and five batteries and each have a Manfrotto tripod as handle and to easily deploy them somewhere when needed - this setup have been working very well for us www.idonothaveaboss.com and www.ankanwildandcrazy.com ironic enough this picture was shot on our Canon camera
Well for a good still picture i would go to my Dslr anytime, fortunately you can mix and match those in to your footage as you please.
And don't put all your eggs in one basket, or 2 similar baskets.