thinking of buying Zgemma....2S or H.2S

OK looked around and nothing comes close to these boxes esp for dual tuners. Slightly confused as to the difference between two versions. Considering that both versions has low ROM/RAM, will the CPU or any hardware upgrade on H.2S worth extra money over 2S? Also how good are range on remotes?

Do these boxes support internal HD? if not how good are USB recording and playback?

Thanks.