Hi scrowe,
Sorry for the late reply. If you are intent on buying these films, my recommendation would be to go for the Eureka 1&2 set. They are pretty comprehensive in terms of the PQ and extras:
Want to see Jackie Chan's career defining Police Story finally done justice? Read our review of Eureka's Police Story Blu-ray
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Want to see Jackie Chan's career defining Police Story 2 finally done justice? Read our review of Eureka's Police Story 2 Blu-ray
www.avforums.com
Although stranger things have happened, I believe its a rights issue which is stopping Eureka/other current UK boutique label releasing PS3 onto UK blu-ray for the forseeable, so the HK Rescue disc might be the best option for Part 3 (along with Eureka for 1 and 2).
Part 4 is difficult to get on Blu-ray as far as I’m aware (although not actually checked). I have an international cut on DVD and a longer Japanese cut on dvd (might even be VCD!). I’ve never sought to get it on blu ray for some reason.
As for the film itself - whilst the first 3 has a lot of trademark Chan humour (And this takes getting used if you‘re not used to a certain style in Hong Kong movies, often veering from humour to serious melodrama from scene to scene) - Part 4, or First Strike, is much more of a knockabout action comedy in the vein of his US outings like Rush Hour. It is still a lot of fun, with the usual great set pieces and stunts, but its more of a Bond homage, and feels more of a departure from the orginal three films.