In your shoes I would contact a broker to scour the market for you to find the best deal for you. Given your loan to valuation ratio you should be able to get the very best of the deals available.

You didn't mention what the standard variable rate is that A&L are offering when your tracker expires. I was pleasantly surprised with my lender that when I came off my 4.99% fixed rate in December and went on to their SVR which was 1% above BOE base rate (1.5% in total). It is often worth checking what the default deal is.