Replying to Which rail? +k for any help!

so i know there will be alot of people saying... "Searchbar!" or "Build-a-jib cult!" well i did post this in build a jib but it gets much less traffic then ski gabber so hoped this would be ok. My friend and i are building a double barrel pvc rail, and were wondering whether it would be better to have one 16 foot rail or two seperate 8 foot rails. we thought the advantage to the two would be we could create multiple setups, but then were worried about the gap between the two. which would be better! plus karma for any good help!