alternatives

Guys, hoping to get a steer on a new battery, mines dead so I need to get a new one, what's the alternatives to a OEM one ?

I need a new helmet after i crashed in my old one. I´m looking at these: Arai Chaser V Shoei GT-air Schubert C3 pro Schubert S2 Got any experience with any of them, then please chime in. Would be appreciated :-) Alternatives is also welcome... Thanks!