Definitely get a firestore. I myself have a Jvc gy hd110u, and the firestore I have with it is the DR HD100 (it’s actually designed for use with the JVC camera). I can shoot either .m2t or .mov. You can only shoot .mov if you have final cut pro 6 or higher. For some reason it’s the only software with a quicktime hdv reader. So unfortunately I can only edit the .mov files on my mac, and not on my PC which has Avid (i can only use the .m2t files).
Still it’s been worth every penny. Shooting both on tape and the firestore simultaneously for a hard copy & quick to edit files. As far as I know, it can capture whatever the camera puts out. The 110u can shoot 24/25/30p and it can capture those framerates. If you have the 200 you can shoot 1080i on it.
Hope this answers your question.