Even if you can hit high speeds, some specific examples I'd like to mention that kbryc08's already hinted at are:
Torrent Health: the torrent's not going to go anywhere anytime soon if it has 1 seed uploading at 5kbps to 10 leechers. This happens far too often even in the modern era of "hi-speed" because the people who are usually nice enough to stick around for months, even years after a torrent was first created and keep seeding usually don't do it for just one -- they do it for multiple torrents. So the way they see it, they're seeding stuff at like 50 kbps daily and are doing their part to keep the filesharing movement going, but the way you see it is you see only one seed seeding to you at 0.5kbps and you're like ;_________; .
Your ISP: many service providers, Comcast being one of the most widely-recognized for having done so, are starting to wage a covert war against BitTorrent, the consequence of which is that if your ISP recognizes use of BitTorrent it can initiate measures which limit your download and upload speeds to below 30 kbps. I and many other individuals have noticed this happening to us in the past 2 years (personally, in the last 4 months) and the trend seems to be on the rise in the USA. Typically, the more seeds the torrent has, the less noticeable this is.
General Douchery of Leechers: perhaps the biggest problem facing BitTorrent, one which has been with it ever since it first took off 5+ years ago, is that there is no way to force people to seed to you as well as they are downloading from you. I'll give you a good example of what I mean: often, I'll connect to an old hentai torrent that has one seed and two or three leechers. One has 30% completion, another 60%, and the third 90%. I'm sitting at 0% initially, okay? So, none of them connects to me. Not one. Eventually I get my fair turn with the seed, and he seeds me a bit, and after an hour I'm at 5% completion. Now what happens? The guy at 30% completion connects to me and requests half of the data I've gotten which would bump him up to 32.5% completion. I give it to him at 100 kbps, proving he's on a hi-speed connection, but what does he do? Gives me nothing. After two strikes, I block his IP. But the situation is no different with the other two leeches. They're selfish scum who are capable of high DL and UL speeds but refuse to help me out and then turn around and ask me to help them out. Pieces of trash. >_< Sadly, this is pretty common -- and what ends up happening is that all four of us have to stay connected to the Internet for one day, possible two days straight, making 5-minute connections to the seed and getting the file that we all could have gotten in under 2 hours if we had worked as a team.
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The reason I'm telling you all this is because if you take kbryc08's advice, test your DL and UL maximum speeds, and you discover that:
- you can handle hi-speed, I don't want you to think that you're still doing something wrong. You may be doing nothing wrong and have just been connecting to really shitty shares.
- you can't handle hi-speed, I don't want you to think that when you decide to upgrade to a hi-speed Internet service provider that you're going to automagically download all your hentai at the speed of light.
Whether you like Naruto or not, the best honest-to-God advice I have for you is to go to Dattebayo's website and to test-download the newest release of Naruto; although if it came out less than 5 hours ago you'll want to wait just a bit. Usually I can get the first episode in under 2 hours if I join the swarm ~instantaneously; I get it in under 30 minutes if I get it in the first 24. I don't think you'll ever find a better seeded, better UL'ed torrent than a Naruto episode because (1) Narutards are many and (2) most Narutards aren't smart enough to figure out how to screw over their fellow peers even if they wanted to.
