Slip on or full system

I want to get a full system but dont have the cash and was wondering if a good slip on like arata or sato will give me the sound and extra H.P. like the Full system does. Is there a alrage difference between the two other then weight. I heard many good thing about the new arata. Any insight would be great

2 Brothers V.A.L.E. Slip On in Carbon Fiber is the shizznitttt!!! I have used an Arata, Micron, D+D, and a Sato and havent found one that is nearly as cost effective, provides the seat of the pants horsepower increase, or that sounds any where near what the 2 Brothers does. Very Throaty, really picks up the midrange, and the carbon fiber can runs so cool you can put your hand on it directly after a ride. I bought mine from a dealer on Ebay, I'll post the link to his store at the end of the thread. Buy what you like and what makes you happy, this is just my suggestion......WEEEEEEEEEEEEEEEEEEEEE!!!!!!!!!!!!!

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1,1&item=4563816509&sspagename=STRK%3AMEWN%3AIT