I upgraded from my rail to an Empire axe that I got used for about $325 with parts and everything. If you're willing to go used and pay a bit extra you can find something higher end for a decent price. You could even get a used rail and use the extra money on paint or other gear.
Otherwise If you'd rather buy new, have to say the rail is a great little gun and is definitely fun to use! Have to mention that mine in particular seemed a bit finicky, but others were fine. Still recommend it though.
Thanks guys, I got an Axe and gotta say it's great so far. I have yet to take it to the field (going tomorrow) but from shooting in my backyard and feeling it in my hands I could tell it was something awesome!