We had a great three-day stay at Alexandar II. It is a small hotel, one of the reasons I chose it. It was clean, the staff were really good and friendly people, the breakfast was incredibly tasty and the beds were comfortable to sleep in. Also, the location was fantastic, not noisy, but very close to Macedonia square and the old bazar (and also to malls if shopping is your thing), and all sorts of touristy attractions.
We highly recommend Alexandar II, and definitely stay there again when we return to Skopje one day!