I've stayed at Hard Rock and Royal Pacific at Universal. They were fun resorts in good locations but I definitely would not consider them 'true luxury products'. The rooms were probably on a par with WDW rooms. The service, for me, was not as good as Disney. I've only stayed at each once but the check in experience has been poor both times, and was actually rude at Hard Rock. They made us feel unwelcome because we didn't book directly (we weren't actually able to from the UK!). We stayed club level at Royal Pacific this year, so I can't compare this to any of our DVC stays, but compared to the one club level stay we did at WDW it was nowhere near the same standard.I have stayed in Loews, but not at Universal.
Are the ones at Universal true luxury products?
I would still stay at Royal Pacific again as I enjoyed the hotel, and I'd like to try Portofino Bay one day, but they're good hotel stays in a great location. They don't come close to luxury hotels, from my experience.
I hope I don't sound like I'm complaining. I didn't stay there, nor do I own DVC, for luxury. I do value convenience and a few 'extras' though!