Been using Flashget years before Firefox.
Have tried IDM, FDM, orbit, getright, IDA, wxdownloadfast, DAP (in its early years, don't even think about it now.) firefox's inbuilt DTA.
Other old ones I used in the past NetAnts, NetPumper (both have malware but I have used patched versions.)
Been leeching for years so I have to refine my skills and keep testing new tools. My verdict, Flashget Classic v1.73 (the first free version without the adware and before the new guys added bloat to an excellent piece of software and crapped it) is the best download manager of them all. Though it has fewer optons, it is the leanest, safest and most reliable download manager. Unlike the versions thereafter (i.e. after v1.73), there is no problem of overdownloading with some links and is freeware.
wxdownload fast is also great (and its open source

)
FDM is also good.
You can download RS premium links from all download managers using your RS session cookie string as the referrer and your corresponding user name and password.
The thing I hate about IDM is that first its shareware (that may or may not be an issue for most fellows) and second it takes over the system. Though it dynamic multi part downloading is indeed very fast, it corrupts things (it did for me) after multiple retries, especially if you are on very high or very low speeds.
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