If only the rooms would have been like the ones they have on the hotel's website. The room we stayed in (room 132) was dirty, dusty and the bathroom was like a school gym shower from the 70s. I don't think that the cleaning staff had opened the window to let some fresh air in for at least a year.

The carpet and walls in the corridor had more stains than the carpet in my daughter's creche.

Dirty!

You really need a car to get into town as the hotel is in an industrial estate.Check in was ok. We asked for late check out but were told ther was none. (even though we had agreed on that when booked) Quite expensive to stay considering how far away it was. Wireless free which was good. Room size quite large and we booked a double room and got 2 large double bed (which we put together to make a mega bed!)
The gym opening times were lousy especially at the weekends.
Food prices in the reseraunt extremely expensive (better to go to town) Breakfast was ok.
Overall its fine just to sleep there, nothing more.

I work in DK and wanted to have a "get away from it all" few days by the sea. Sønderborg turned out to be a wonderful place for such a venture: it's got a terrific hike & bike trail by the beach, a spa in the adjoining town, Kråsten (15 km), and an overall delightful, idyllic ambience. But the hotel was a major disappointment, definitely not 4 stars! It has a 70s kind of plain style to it and although some of the rooms have been renovated, it's all very lacklustre. The bathrooms do not have any of the amenities you'd expect in a fine hotel and both the sauna and swimming pool are old-fashioned. The breakfast is ok, but not great, although the ladies there work very hard. As to the reception, the service depends entirely on who's on duty. The worst receptionist was Sandra who could not point out the bus station on the map and seemed to prefer surfing online to being a receptionist. But there were some friendly staff as well. My general sentiment was that such a neat town would deserve a proper 4-star hotel; this one sure isn't it. Finally, I second another reviewer's recommendation of the Poseidon restaurant: great food, great service.

Stayed 2 nights at the Comwell last week on a business trip. Hotel is centrally located in Sonderborg, easy walking distance to the fjord, castle, shopping areas, & restaurants. Staff was 'efficient', but not overly friendly. English is well understood.
Rooms are 'stark' & basic - beds, TV, minibar, towels - and 'well used' - but very clean. Not overly large, but adequate for one or 2 people.
Breakfast buffet, included in the room, is very good by European standards.
Restaurant & bar are VERY expensive - but there are several very good restaurants within a 5 minute walk - so not a major issue.
The pool/sauna & excersize room are the highlight of the hotel.

Overall, a solid 3 star, with a plus for the pool/sauna/excersize room.