Dear abc111,
I took already several exams included IELTs. Most exams have 4 components: to read, understand, write and speak. Depending on her/your capabilities, if you were able to read and understand the Life in the UK book (3rd Ed.) you would probably will do well with something like the Cambridge First Certificate Cambridge-CFC. The IELTS equivalent is called "General". If you obtain a 60% you will score enough for the UKBA requirement.
This I can contribute:
1. IELTS test structure is more demanding in the student, not only request a proper answer but also requests you to "rationally" think the answer. Example: the "listening" component of the General test requires you to listen to a recording and then answer correctly to some questions. The recording could be spoken in several accents (Australian, English, New Zealander) and the answer ought to be only one word. In the recording two "probable" answers are given and you are expected to point at the right one, but you probably will have no time to think about it while you write both down. And with all this happening the recording will be played ONLY ONCE!
2. In contrast, the Cambridge First Certificate has considered the use of the language in context (you live in UK, you speak British) and the accent in the recordings is only standard BBC English. The construction of the questions expects you to understand the meaning but not to "spot tricks", say. The level of grammar is more realistic and the recordings are played at least twice.
3. According to UKBA website the IELTS test has a validity of only 2 years, while the CFC is valid for good. It implies that, if for any reason you need to present the English qualification again later, if you choose to do IELTS after 2 years you will have to do it again.
4. To this date (and always depending where you would take the test) IELTS is more expensive than CFC. Here in UK CFC is around 119 pounds. IELSTs same level 134 pounds.
Try the links below for trial tests and study materials for both. It is free!
www.cambridgeesol.org/resources/learner/index.html
http://www.ielts.org/test_takers_inform ... ample.aspx
There are several different tests in offer. Do some research online and Good luck!
