HTC EVO 4G

I am a new EVO owner and I was just wondering am I wasting my time installing Advanced Task Killer on my EVO? The reason I ask is b/c when I was with Verizon wireless I had the Motorola DROID X and the Samsung Fascinate and the Verizon rep I dealt with informed me that if I didn't have Advanced Task Killer my smartphone would be really slow. When I purchased my EVO last night the Sprint sales rep I dealt with told me not to install Advanced Task Killer on my EVO or it will dramatically slow it down, whats the deal here? Also how do I install swype texting on my EVO I found a video on youtube that walks you through the process but when I get to where it is time to install the swype file it says that it cannot install it. If any of you fellow ...
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