The Consumer Credit Act 2006( http://www.opsi.gov.uk/acts/acts2006/ukpga_20060014_en_1) imposes a test upon loan agreements in that that a Court may intervene if the relationship between the creditor and debtor is considered to be "unfair" in relation to any aspect of the agreement.
There are no examples given of what is unfair and it is, sadly, undefined. It is a recent act so there are likely to be quite a few inconsistent decisions by Court until precedents are settled upon. The OFT has not issued any guidelines either.
The Court is entitled to look at (amongst other things) interest, the way in which the agreement is drafted, harrassmnet, coercement, misleading statements, pre-credit checks upon the debts and the manner in which the lender has dealt with the consumer.
The Court's powers are very wide to they could vary the agreement, discharge any obligation under it, reduce interest under it.
If you wish to get an opinion on yours you can do your own check (the legislation is not conceptually difficult to understand but there is a lot of it) or contact a consumer lawyer by using the following land registry website:-
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