Because the "obey download/upload speed limit" setting is application-wide, it affects all running copies of FlashFXP.. It would be nice if this setting could be controlled on a per-site basis, because ie. you could be using an ftp site that asks you to obey a certain speed limit, and if you use that site every now and then, you have to go into preferences and change that there each time, also affecting any other flashfxp sessions you have running, effectively strangling them also.
This subject has been slightly touched before here:
http://forum.flashfxp.com/showthread...=&threadid=431
..but that was more of a bug-report than a feature suggestion.