Stayed here during a work trip to Serbia, and overall pleased with the hotel. Rooms are spacious and clean, and staff generally helpful, though fatalistic (could be a national characteristic). A little out of the centre, and a walk to the castle takes around 20-30 mins (much of it uphill).

Pricing was reasonable, and I would stay here again. Beware the rush hour though if you require car transportation - the hotel stands on a busy one-way street, which is gridlocked from 8-10am. ALSO - if you're from a country (like the UK) with draconian anti-smoking legislation, you'll find all the indoor puffing here (and throughout Serbia) a little unpleasant (or a welcome relief, depending on your predilection).

The hotel is not really in the centre and I have found it with some difficulties the evening I arrived in Belgrade.
Anyway, it is near the railways station and this has been a good advantage when I took the train early in the morning to visit Novi Sad and Subotica.
The breakfast I had in the morning was really good and the room was quite cosy even though not too big.
In the period I stayed at the hotel there were not a lot of other travellers except on my last day because there was a marathon or something similar.
The price I paid for the three night I stayed there (in a single) was really cheap considering the service and the quality of the stay.

I was lucky enough to recentlly visit Belgrade and stayed at the Hotel Rex. The hotel is well situated and it's a pleasant 20 minute stroll to the city centre with a variety of decent small bars and cafes along the way.

The hotel receptionist was very good and took care of details such as arranging a taxi the following morning for the airport run and arranging early morning call etc. The hotel really does look like an office block from the outside but inside has all the practical necessities required. The room was perfectly adequate for my requirements, the bed was comfortable, the tv worked as did the aircon and the room was well cleaned.

The breakfast here is eminently adequate, coffee, tea, juices, cereal, bread rolls, bread for toast, cheeses, meats and a selection from the hot plate. (You can tell that I was more than happy with the hospitality here)

So, all in all, a perfectly good choice of hotel in a safe area and for the price that they charge, you can't go wrong. I booked through Ocopus travel and paid around £37.00. Bargain.

Very good location, 10 min walking from bus and railway station, 20-30 min from old city center and one bus station from Sava center (conference center). They sometimes have special offers so I paid 40E per night in single room.
Staff are really friendly but they do not know a lots about touris attractions and they do not have a city map, but for me these it did not matter. In room Wi-Fi is little bit slow.
Room was comfortable, clean with air condition and small Tv (approximately 40 programs).
In the courtyard of the hotel is terrace where you can drink a beer or coffee in the shade. Around the hotel is a lots of small fast-food restaurants and shops.

I recommend this hotel for tourist and business travel.