Don't hesitate on looking at the legend line. I myself own about 8 st croix rods. I've Got two legend tournaments one fast action one extra fast action, both spinning for my finesse approaches. I absolutely love my fast action Ned rig rod and have only caught 3 or so fish on my other as my season in northern Utah about over. I couldn't recommend the rods enough.
I know you'd get a medium for your casting reel, but you'd notice the difference right away between the scIII and the SCIV as well as the FRS when you load it up.When i first picked up a legend rod i felt like i would snap it (i haven't and I've gotten huge carp and cats on it) on the first big fish.
My glass rod took my cranking game to a whole other level this year in terms of hook ups, but it's more suited for treble hooked baits like square bills and such. Not great for your under spins and swim jigs.
I can only recommend up to the legend tournament line as i don't own the X, extreme or elite.
Also...i feel the pain of having the avid x break. I broke my MHM this year and they don't make that model anymore. They gave me a victory instead and I'm still not sure how i feel about it.