Being an Irish man who moved here 18 months ago maybe i can offer a bit more help.
If you have never been to china before, it will be a culture shock but HK is more western that say mainland China. (Thanks Brits!)
Depending on your salary grade, the city can mean different things. If you find a comfortable place in a building you like with a reasonable commute,
your quality of life should be fine. Much more things to see and do here than back home. If crowds and ignorant locals dont bother you, you will love the city.
People can be rude but i find a smile goes a long way to be accepted. Yes you will get it thrown back at you now and then but is any other city that different?
If you are single, well HK is a playground. Im spoken for so............
Money rules so again, if your salary is good, things get much easier.
People work hard here and play hard, i found it easy to make friends here but keeping them is another thing, busy lives can take a toll on friendships here.
As for food, well you old Irish favorites are hard to find, plenty of imported British favs but pricy, which is fair enough considering its shipped half way around the world.
As others have said, there have been plenty of posts looking for advice for newbies so check them out.
Considering the way the Irish economy is going, will you have a job in a years time? The way i look at it, a few years in HK looks great on your CV and cant hurt your career path any.
Hope I've been of some help.
D.