Went here fairly early (7ish) on a Friday evening as we knew from other reviews that the place gets crowded, and lucky that we did as we got the last table. Within a few minutes of sitting down there were people queuing outside the door, apparently normal according to the waitress, despite the -7 or 8C temperature, snow flurries and wind. And there was the downside - sat close to the door which people sometimes just left open as they queued, giving a cold draft. To be fair, staff did their best to keep the door closed.
As others have said, this restaurant is a favourite of students and younger people, but there were some families and older couples, like us - we definitely didn't feel out of place. The place is quite crowded, though not cramped, and waiting staff were constantly on the move - very busy with both eat-in and take-aways.
Service was pretty rapid, in seating us and bringing menus, then taking orders and bringing food. Turnover is clearly quite swift, although people lingering over coffee didn't seem to be pressured into leaving. Food was good and, if not authentic Thai (per another reviewer), certainly satisfied us - not the best Thai we've had but we thought very good and good-sized portions.
Of course, as others have said, the major attraction is value for money - in our case a shared (and quite large) chicken satay starter, 2 good sized mains (one chicken and one prawn) and 2 non-alcoholic beers (they don't serve alcohol) at 385NOK - around £45. That's an excellent price for a decent dinner in Norway; we went elsewhere for 2 glasses of fairly ordinary wine later and that came to nearly £20.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.