I see you are in UK (this makes a difference!). I recently subscribed to the BSG website (British Sugarcraft Guild). It is not only a great source of UK specific information but has some excellent recipes.
There is a fantastic recipe called HD sponge recipe which is very moist and has a close crumb, so is suitable for carving. It also keeps very well. It is clearly the main recipe used by a large number of the members. You must use Mc Dougalls Sponge Flour and block Stork and follow instructions carefully. This includes covering your tin with another larger inverted tin. This gives a totally flat top and prevents the outside cooking befor the middle. Recipe quantities are given for every size tin, with flavour variations. I was so excited after I tried this recipe and the fantastic feedback I had. Now I have found it I will never use another for sponge cakes. I was a little sceptical when I first read the recipe as in some ways it’s not a lot different from Victoria Sponge, but the secret is in the specific ingredients and the method. (PS. Extra tip – put piece of silicone paper over the top of cake tin before baking so that it doesn’t stick to covering tin). Would love to hear what you think.