I have had Tamworths, Iron ages and some that where crossed so many times that there paremtage was very questionable!!
My first Tamworths tasted great but where a bit on the fatty side. The Iron ages had a very strong taste and I know have a couple in the field along with some yet untasted GOS.
The first crosses where disappointing, so the rest became bacon, sausage and gammon.
Mine where fed on Sow and weaner nuts through out and free range in a large paddock eating there way through the field. Once you have had ypur own pork you will never want to go back.
Consider pig keeping as a adventure....it really doesnt matter what you have as next time you can try something else.
The key is not to over feed, yes, fat improves the flavour, but you dont want more fat than meat.