My CVT HR-V isn't perfect. The auto idle stop is a bit temperamental but perhaps it (and myself) doesn't like winters. The touch panel control for the heating and ventilation should be illegal as it's difficult to adjust anything without taking eyes off the road (but many new vehicles have the same failing). These issues aside, it's an excellent vehicle which has the high driving position, generous space for people (but note that the EX has less headroom) and baggage and is relatively economical (50 mpg is feasible on longer trips - last summer it gave 53 mpg over 2000 miles to/from/around Scotland but I tried to avoid motorways).
Why so few? Until mid-2016 supply was rationed due, I think, the factory struggling to get to full speed and priority being given to north America. However, the situation has now improved and since mid-2017 hthe Honda factory staff in Swindon have been allowed to have the HR-V as a lease vehicle (so I've been seeing a lot more on the roads in Swindon).
I deliberately bought an ex-demonstrator on the basis that the dealer had 6 months to sort out any bugs (he admitted that there had been some). I also saved a few thousand £££s. You can find these vehicles listed in the used vehicle section of the Honda UK website. If thinking of older HR-Vs, I would avoid the first 6 months of production (ie 65 registration) as these seem to have been the most buggy. I reckon that the bugs are now pretty well sorted and, most likely, feedback from factory staff is more effective than complaining customers for addressing any residual issues. The current rumour is that when the HR-V gets a refresh then UK stock will start coming from Japan.
There's more HR-V discussion in the HR-V forum
https://www.hrvforums.co.uk/index.php. Probably the longest (and ongoing) discussion is about the auto idle stop. Nonetheless, that forum is sufficiently quiet to suggest that most HR-V owners haven't got anything to complain about.