BT4's, Deltas, Tippmann 98's, A5's & original X7's are a well out dated design, inefficient, loud, heavy, inaccurate, massive profile, any tourney marker is going to put them to shame.
Form over function with most scenario markers, scenario marker are designed to look cool, like a military weapon, wasting money/weight on fake mags, scopes, stocks, lasers, flashlights etc etc where as a tourney marker is designed purely to sling as much paint in your opposition direction.
First marker, personally i would suggest a poppit marker, less to go wrong whilst your new to it all, keep an eye out for mini's, axe's, eteks, older egos. Try and get a hold of them all before you buy, get yourself down to your local walkon, and have a shoot of some different markers, as some people cant get on with how compact the mini is, or the trigger on this marker etc, some find egos and eteks to loud, still going to be quieter than any of the markers i mentioned at the top of this post.
Hope this helps.