Unsprung weight matters. Rota wheels are not forged they are cast. That is not to say they are rubbish - they are extensively tested - but to make cast wheels as strong as forged wheels you need to use more metal.
Rays Volk make a variety of wheels but genuine Te37s are forged. Its a more expensive process but makes for stronger wheels.
For the street your Rotas will probably be fine - there are lots around - but for serious track use people will probably pay more for forged wheels or even for wheels made of lighter metals.