The Sainsbury's Bank Mortgage offered everything I needed, including 100% loan, low interest and an easy to use cheque book to give access to spare money on the account. Over payments, under payments were allowed to a certain limit and it was easy to switch to a new Sainsbury's bank product.

To be honest, I could have got any of many 'cheaper' mortgages, but the fact is that the mortgage from Sainsburys bank was one of the most flexible I found.

You can make a lump payment and they will either recalculate your payments or your loan duration, you can make overpayments or take repayment holidays as long as the repayments add up at the end of the year, you can even pay off the whole amount (luck and the lottery allowing) - all with no penalty.

The addition of 30000 reward points every December is worth £150 off your shopping at Sainsbury's (with it now being Nectar points it's probably even better).
For a smallish mortgage such as mine (minimum £25000), the 30,000 points dropped the price into the lower end of the market. Add in the no penalty flexibility and it's obvious why this became the mortgage for me.