I believe I've come to the conclusion that 'cheap and throw away after' might be the better way to go. I can never seem to be able to remove all the paint at the end of the job, so I end up leaving the brush in soak, in some spirit or other, only to find it dried up and no cleaner a few months later. Too cheap and I grant you, you'll be picking hairs out of your handiwork all the time, but fairly cheap and 'blow the cleaning' might prove a good compromise.