Personally I hate the word Hectopascals. I don't find it as easy to say as millibars, nor do I find it easy to change the habits of 15 years of controlling. But as with others, rules are rules and I don't want to lose my licence by failing checks on something so simple, so I will continue to at least try to say the right thing. Professionalism says that is the least I should do. So far in UK I've not noticed pilots not saying it when required, but all of us seem to avoid it when we can...
Cheers,
Northerner
"Keep smiling... It makes people wonder what you're up to..."