Easton L9.0 and new 2015 Salvo Scandium (SP15SVS) are basically the same bat, one piece singlewall, L9.0 came out in 2013/2014. Both have progressive endloads (1 oz endload for 26 oz bat, 2 oz endload for 27 oz bat). Easton L7.0 is a 2-piece singlewall with composite handle (same progressive endload). Easton L7.0 would have a softer/more flexible handle while the Easton L9.0 would have a stiffer handle. I would think the Easton L7.0 would hit the 44/375 softballs better than then the L9.0 but the L9.0 would do better with the 52/300 softballs.
These are fairly close to the 2012 Salvo scandium as well (SP12SVS) but I am pretty sure that did not have a progressive endload. Check out this thread for a write up on a number of different singlewalls, post # 54 ( we compared the new Evil Prototype singlewall to the Anderson OG Nanotek, Anderson Flex, Demarini White Steel, Demarini Raw Steel, Demarini Ultimate Weapon, & Easton L9.0):
http://forums.softballfans.com/showthread.php?t=1413852&page=4
Cannot go wrong with either the Salvo Scandium, L9.0 or L7.0. The Anderson Flex will probably be a more durable bat but I don't think it has as much pop & its hard to get past that metal ting sound it produces. Hopefully Evil sports will get their Evil Prototype ASA approved soon, I liked that bat a lot as well
JJ