As far as helmets go, as long as it is SNELL rated it is fine.
A lot of people question why I refuse to buy a DOT only helmet, and quite simply it is for security. DOT helmets are inspected and claim to have met that requirement from the manufacturer, it is not independently tested. However, to obtain a SNELL rating, the SNELL Organization independently tests helmets and provides them with this.
So, why do I wear only SNELL, regardless of on the street or track? Because I trust an independent agency over the corporation trying to sell its helmet. Additionally, what happens if they claim it is DOT and it isn't? They get fined, and told to meet the standards. That's it, not a huge punishment.
So, who will you put your head in? A company's trust, or an outside, noninterested investigative third party?
To answer your question, helmets that I've had:
Bell Star - fantastic helmet. Runs big.
Shoei X-11 - probably my favorite helmet, helped me survive a 90 mph bump on the head.
Scorpion EXO-1000 - heavy, not that great. Only feature I liked was the drop down sun visor. Held up to two crashes (120mph and 95mph), although I shouldn't have been wearing it in the second one .I was very lucky.
HJC CL-16 - good street helmet, wouldn't track it personally.
HJC RPS-10 - probably the only helmet that comes remotely close to the X11. Best thing about it is how wide the visor is, I can see soooooo much more (although, for a street rider this isn't as important)