Uh, actually you're all wrong!
Try DAP first of all.
IMHO, it is the fastest and the rest pale in comparison. However, it does have a lot of spyware, so watch out for that. I've been there, done that, so I know that Flashget is fast, but its interface is kinda clunky and it's not really that "fast".
Internet Download Manager is great, I have a copy if you want one. But I still recommend getting Download Accelerator Plus. I have the premium version, so let me know if you want it badly!!!
Pieace out,
C.K.