R3 seems to be a bit hit and miss sometimes although i don't have other regions of the same dvd to compare to.. spiderman 3 was great, the punisher was awful, dawn of the dead pretty bad, indiana jones great. not watched danny the dog yet but i've heard the picture on that is ok but not great.. i suppose it's one of those situations where you buy a dvd and aren't impressed by the PQ then just assume it's cos its R3, when in reality the PQ on the other regions might be crap too.
I usually find that region 3 DVDs are as good as their region 2/region 1 counterparts on new releases, particularly of the last couple of years. However older releases of older films tend to be a very mixed bag. More recently I've been put off region 3 DVDs basically because CD wow has put their prices up so that they are more comparable with region 1/region 2 DVD prices, maybe only a pound cheaper. For me that defeats the object of buying region 3 DVDs so now I wait for a few months after the region 2 release to pick them up closer to £8.