Iwata Kustom CS all the way everyday Stu, I have 2 and they are a workhorse of a brush. Mid level when it comes to cost but I have not had a moments bother with them considering the amount of paint that has flowed through them
Give us a shout if want me to price a brush up for you Stu
Andy, I have used the gravity fed Neo brush recently to try - And they are not bad for the money!