funny thing, in a pistol length, I'd take the 7-30 every time, but in a carbine, I'd take the 30-30...not sure why, but I do...and have bought accordingly....
I don't think you can lose with either, if you are a cast bullet shooter, the 30-30 is better, if you want to later rechamber to 309 JDJ or 30-30 AI the 30-30 is better.  When you load spitzer 125-130 grian bullets in the 30-30 alot of the ballistic edge of the 7x30 is pared down.  But again, I love both.
regards,
 Graycg