I wouldn't worry about Frequency response stats much. They aren't an exact comparision and most no one can actualy hear to the extream highs most any speaker can play to. I personaly can not hear above around 17.5K hz. Using your own ears is the only way you should compare speakers.
Also, papers not a bad thing, its actualy makes a really good speaker metarial. Its all about execution, it can be cheap or very high quality. The only reason you should even bother with knowing the material a speaker cone is made out of is for longevity. The Alpine Type S should last you a good long time, so no worry there.
The alpines are a decent speaker although not high on my list. I'm not a big fan of them, in sound only mind you. You need to be the judge of that. Take a listen to them against some compeditors like JL, polk, eclipse, boston acoustic, Pioneer, rockford fosgate, focal.....ou get the idea