Asking for information about 'the best' of anything is simply going to get you a lot of yelling from the fanciers of different makes/styles. What do other people you know wear? Does your FD have a preferred make? What is worn by neighbouring FD's? If there are no satisfactory answers to those questions, find a local supplier and go and try on different makes/styles. Then you'll know what you prefer.
This maybe a stupid question but why do you need a second helmet for extrication. I honestly dont know! the department that I am on we never do extrication because the speed limits in our response area are to low for any major accidents so I dont know a whole lot about the subject other than how to do it.
Although, like you, we don't do extrication work, I can see the need for a smaller helmet. Firefighting helmets are too large and bulky to wear whilst poking your head into a car doing what you can. Smaller helmets, a bit like construction helmets, are a good idea.