Hi Nigel,
We have a bav34 from 2002. As we used to race an Impala we were never very happy with the original Elstrom sails and struggled to sail at 30 deg apparent. We used Mouse sails from Holeyhead Anglesey to make our new main and genoa. For the main we asked for a flatter cut than the original and longer battens, but not full battens as we wanted to retain our ability to spill wind from the top of the main in a blow. We ordered a good quality Dacron and it sets very well and we are sailing much closer to the wind.
For the genoa we reduced the size to 120% and mouse have a very good way of providing a soft luff to maintain a good shape even when furled quite small. This consists of a series of rectangular flat sections of foam sewn into pockets which get shorter as they progress from the luff. We are very happy with the result and you would not believe that you were sailing the same boat. Not sure that a radial cut is a good idea if you are using a furler, but Mouse would advise.
The price will be better than you will find on the South Coast and this will not compromise the quality and detail finish. I have no connection with Mouse but they have always given me what I have asked for.