Which one is easier, IELTS or TOEFL? How much time is required for the preparation if I have good English? (ANSWERED!)

I wrote this answer over two years ago when I was in my final year in college. However, I did not end up going for masters as I had a decent job offer in India. Now, I wrote the IELTS again in Bangalore on Nov 13th, 2014. As a result of the experiences, I think the following should also be thought of while applying:

1. IELTS is organized by three different organizations. The British Council, IDP and some other "non-profit". Four of us friends registered for it at the same date, and we ended up going to different test centers because we had registered through different websites. And we realized that only on the date of the test!
2. The guys at the British Council are very unclear on how they send scores to universities. The lady who was in charge of the examination gave as an answer as vague as an answer can get.
3. The scores are sent by Speed Post to you. My friend missed one character in her address and the postman took the scorecard back. It took 10 days and at least half a dozen phone calls to get the scorecard back.
4. Sometimes, they just don't release the scorecard on time. Mine got delayed for more than two weeks because they were doing some kind extra checking for my sheet. I missed a deadline because of that.
5. They require you to get a clear photocopy of your passport. They made me walk around 1-2 kilometers to get another one, and when I got it, they said that they need a colored one. I just walked off after that.
6. The speaking test is at a different date. People are allotted slots accordingly. However, if you are a girl/woman in India, there is no guarantee that you would give a day slot. My friend was made to interview at 6.30 pm and then made to walk for at least 3-4 km to get a colored photocopy in pitch black roads.
7. Their re-evaluation process is very slow and cumbersome. I got 6.5/9 in my writing section while I was expecting 7.5-8 since my essays were very good by my standards. I also got 4.5 out of 6 in GRE so I thought it would be fair to expect a decent score in IELTS as well. When I called up the person for re-evaluation, he said it would take 6-8 weeks and around 50 USD. I just dropped the idea.

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Original Answer:

It is a little difficult to determine which one is easier, but you should keep in mind the following points before opting for one.

IELTS is organized by a bunch of British folks (or should I say the Commonwealth?) while TOEFL is organized by ETS (American). Needless to say, the examinations fit the stereotype.

Although most US universities (MIT, CalTech, UIUC, UofM) accept IELTS, a few like Stanford do not. I did not come across any university in Europe and elsewhere which does not accept IELTS.

All the universities I applied to accepted IELTS.

After a through examination of pros and cons of both, I chose IELTS and attempted it in Mangalore on a fine day in Oct 2012, got a score of 8 (out of 9).

From my perspective, the differences are as follows:

• Unlike ETS, IELTS doesn't say that the scores would be not be authenticated unless they are sent by them. As a result, you do not have to specifically send scores through IELTS. However, for TOEFL, you need to send scores via ETS and pay 35 USD for every extra university, you're given four free ones.
• Lengthwise, they're almost the same (around 3-4 hours).
• IELTS is paper-based while you'd be staring at a screen in TOEFL
• Since you write on paper, it might be very difficult for you to edit what you've written in IELTS, while in TOEFL, as it is computer-based, it is relatively easier to edit. People who have forgotten the art of writing on paper may find it difficult in IELTS (I did).
• IELTS is generally organized in 3-4 star hotels (in India at least), while TOEFL is usually conducted in a cramped cyber-cafe turned into an exam center (in Bangalore).
• In TOEFL, only American spellings and accents are used, while in IELTS, a variety of spellings and accents, including the British and the American ones, are used.
• While you speak to a "trained professional" in IELTS, you speak into a microphone in TOEFL. In TOEFL, a friend of mine complained of disturbances around him while he was speaking. I found my experience really good, had a nice little chat with an old lady about politics and stuff.
• My friends who wrote TOEFL, generally complained of headaches at the fag end the exam, mostly because of staring into the screen for 3-4 hours continuously. Those who wrote IELTS felt as we were writing our tenth standard English board examination, pretty smooth, were served cookies and coffee after the exam.
• Applying for IELTS is a little tricky, first you register on their website, then you send photographs by snail mail to them. It is completely done online for TOEFL. I had some trouble doing it online, so filled up a (paper-based) form and sent a demand draft for payment.
• Overall, IELTS feels of more "quality" than TOEFL, but if you're applying to Stanford, TOEFL is the test for you.