I don't think they sell too well, especially here in the US. I thought it might do good in countries that have engine size limits for certain riders, but maybe the large price tag is keeping people away. It's a shame, because I'm sure it would be a great city bike.
I wouldn't let the slow sales dissuade you from getting one if you have no need for the extra power or fancier bits on the 800. I'm sure it's every bit as fun to ride around town is its big brother.
I had a test ride on the 62 before buying the classic(purely because of the looks), absolutely loved it, you can throw this thing about even better than the 800's and has a feeling of being very nimble. The sound is awesome too when riding.
My wife has a Sixty2 and I have an 800 so I've ridden them both and one after another for immediate comparison on several occasion.. I ride all sorts of bikes and have been doing so for years but I love the scramblers. For me it's an adult mecano kit that I can play about with, modify, customise, personalise and enjoy on short(ish) rides meeting up with mates, go to coffee shops on or pop out for a pint on. For my wife, hers is completely stock except for a lowered seat and some black renthals that she just loves to ride. She has others bikes too including a larger capacity Monster.
Compared to the 800 it's certainly less intimidating if you're a new rider and not as 'urgent' as the 800, you'd expect that (it's half the capacity). It is however, every bit a Ducati, it sounds like a Ducati (that actually surprised me) and it's a dream to ride. Just like my 800, it's an eye-turning machine which attracts a lot of nice comments. Unlike my 800, it has much nicer fuelling (even after I did the 800 race map and fitted a termi).
I don't use the bike to commute daily (I didn't buy it for that) but if I did, the Sixty 2 is a much better choice being very nice to ride and well-behaved. The 800 is great for 'riding' but would wind me up commuting as it's harsh and more snatchy. I saw the Sixty2 described as the ultimate town bike and I can see why. Town bike that is for riding around and enjoying, looking great and having something stylish as opposed to a commuter bike which is typicall boring, economical has storage (top box, under seat etc) and very practical.
It really is a delight to ride fast or slow and handles just like the 800 perhaps even a little more nimble. You will not likely be spinning up the rear and getting the back out like you can with the 800, or popping wheelies (not saying it can't be done) but it's not really about that in the same way as the big brother which can be a stylish ride or a hooligan machine as your mood decides. The Sixty2 feels more refined (certainly in the fuelling department) and will deliver you in style just like the 800. Nobody will know you're riding a smaller bike by the way. It doesn't sound, look or feel small compared to the 800 and unless you're doing a drag-race with an 800, nobody will know you have a smaller engine. There are few about so unlike other bikes, you'll have something much rarer at bike meets which will attract some curiosity.
It's funny, out of the two bikes, the longest ride I've done in one hit was actually on the sixty2. I still love my 800 and for me it was definitely the right choice but I can see how the sixty2 would suit many more people than would be prepared to openly admit. I can see why the 800 is more popular but that doesn't mean it doesn't have a place. It does, very much so, for new and experience riders alike. I'd counsel anyone wondering to go and try one. Finding a demo bike to ride however could be challenging, we only found the 800 on demo and I've not seen any demo sixty 2s. There could however be some low mileage second hand ones out there at the dealers you could test ride.