they are/use different protocols to provide the network, and in the case of bittorent it is more efficient than edonkey (e-mule is on it), as edonkey has server and perhaps some other sources of overhead it needs to handle. However for me a long time BT and e-mule user they are actually the same over long period of use???
Let's put it this way, I was e-mule all the way, but than became Bittorent with Azureus... and now I am e-mule again.
Overall you get between 1:1.5 and 1:2 UL
L ratio with both of them with various short term differences, like if you go for a bitorrent or e-mule file that is rare, than the UL
L ratio can be negative - ie, you UL more than you DL, but if you DL more files at once you offset that problem 100% certain. The fast DL files make up the difference (and there is always plenty of those)...
Just last week e-mule was actually doing more like 1:3 UL
L (so three times more DL than what was uploaded) however this will surely not last for long, and it will go back to a bit below 1:2 as is the long term average.
Overall BT is much faster for single files, and straight away downloads. ie, you want something, like new Linux distro, just save the bittorent file, open it, and it will start downloading at max speed in 5 mins.
With e-mule you actually have to get on the network, spend some time to UL/DL to get up your share statistics, and than it kicks in properly. IMHO it is about a week of being on 24/7 that e-mule starts having such excellent ratios, which than stay that way forever for that installation. So long term = the same, short term BT advantage.
Actually Long term, e-mule advantage, as old files don't dissapear, and there is no silly rar passwords and such, people filter bad files out generally, so just look at the files that lots of people share, and that is all. Ppl can leave comments on e-mule too, so you can see whether the file is what it pretends to be or not.
