Gutenbergs is actually a terrace on the top of Gutenbergs hotel. The view is not overwhelming since the surrunding buildings has the same height, but you get the feeling of sitting on the roof of Riga.
The restaurant is quite expensive for being in Riga, but for us Norwegians the restaurant provided very tasteful food for a reasonable price.
We were there quite early, and when we left there were no free tables. So an idea is to book your table in advance.
The restaurants guests were mainly in their 50s and 60s, but as a couple +/- 30 we loved our visit at this restaurant.