I have no experience of the University of Leicester MBA, but I have a friend studying their MBA by distance learning with the University of Wales.
Their MBA, from what I gather, is good value for money and is a lot less than studying on campus or with other providers.
She studies online and from what I hear she completes assessments and exams online too - so it is very convenient and flexible. (She's a busy manager so studying on campus was not at all suitable.)
I guess the main difference between the two is the level of flexibility and the cost. (A lot of MBAs are around £8 or £10k, and I think my friend pays about £5k)