[Apollo_13]

Get UP 2.01
It is HSFX with a whole lot more!
http://ultrapack.il2war.com/index.php

HSFX is for SEOW (Scorched Earth Online War) and as so is very specific for what they wanted.
UP 2.01 is built up off of the HSFX base and is more orientated for online play amongst the general public with a lot more added to it.

Once UP 2.01 is installed,a MODS folder can be created and added to your game to install separate individual Mods to customize it for Offline play
go to SAS for a special package that will enable your UP 2.01 game so it is ready for installing SAS Mods
http://www.sas1946.com/main/index.php/topic,7949.0.html

UP 2.01 has the most support by the general community, and is the most accepted Mod pack for online play at this time.
HSFX is very user specific and unless you are into there scorched earth campaign then it is somewhat limited for Mods and maps