We stayed at this hotel two nights and found the service friendly, the hotel very clean, and it has a great location right on the main plaza. It was also a good value and offered a nice cash discount. The only negative was that it looked a little dated. The breakfast was average by local standards. The location and value is what makes this place a good deal.

We stayed at the Hotel del Sol two nights.
We had booked over the phone the previous day but upon our arrival the attendant could not find our name and was adamant we did not have a booking. As we insisted he finally found our reservation but decided to look upset at being wrong rather than be nice let alone apologise.
The room itself (a twin as well, looks like they run out of doubles frequently) was very disappointing and not of a 4 star hotel standard. The carpet was not clean. The bathroom tiles were dirty and the overall bathroom needed renovation. The lighting was not bright enough. The airconditioning rattled noisily and smoke smell came through from other rooms (especially in the morning).
The breakfast was a bit of a struggle as the dining area is too small for the number of guests. On the plus side, it does have a nice view over the main square.
I would not go back to this hotel which at 160 Pesos ( approx US54) per night offers bad value for money.

This provincial city boasts beautiful architecture and a bustling streetlife: Hotel del Sol is right in the middle of it all. Facing the main square this hotel was cutting-edge architecture 30 years ago. It seems a little faded but great service and the perfect location more than made up for it.

Rooms are good size with tile and marble bathrooms. Service was outstanding. Underground parking is provided. Beds were comfortable (though my partner and I were given single beds after asking for a double). Breakfast is provided (cheap) in a nice lounge overlooking the main square.

One of the nicest hotels in Tucuman but don't expect The Ritz. We're going back in a few weeks and will give an update.