Are you referring to your man boobs being too big for the former? Or are you referring to you not having the required girth to provide the requisite air tight seal for the latter?
Ha Ha I tried one of them once (manual) pumped it up big as feck. But also painful. In fact i was in agony, then to my horror i had no idea how to realise the pressure Never again, that's all i can say. I thought i would like to share my story