Be aware that if you want to pay off your loan early, some lenders have early settlement clauses and may charge some months interest in fees. At a certain point of the loan it may be cheaper just to continue with the reapayments. If you intend to pay off the loan at the quickest opportnity, you should factor in these charges. It may be a loan with higher APR charges may be better for you if it has better redeption fees.
A flexible repayment loan allows you to make over and underpayments subject to conditions, to suit your financial situation. However it is very likely that the overall intrest payments will be higher than a standard loan. These flexible loans are not that common.
The loans market is very competitive so it pays to shop around. Compare some of the rates available here and you could end up saving some money. There may be other costs also such as set up costs, or if you intend to pay off the loan early, redeption costs as a consideration. There are good secured finance beat that quote personal loans deals around, but only when you know all the options.
Although most lenders advertise an APR you may not qualify for this rate if you don't meet all the lenders criteria.