No, I don't go around looking for just the buffets when I'm in a new place. I might happen to include some if they look appetizing and seem to enjoy a good reputation.
That said, I did go to this restaurant, Istanbul Grilli, while in this city on a stopover. (I ate at a restaurant of another ethnicity using a menu the other night I was here.) They did have a buffet going when I visited. This part of the globe has really short days during the colder months and really long days during the warmer months. Thus, it was dusk when I arrived here to eat, so I don't recall if it was the end of the lunch buffet or the beginning of a dinner buffet, if such a thing even exists. There is also a menu to order from.
At Istanbul Grilli, there seem to be two major serving stations: the one toward the left and further back seems to have the meats, chicken, and main dishes and the one to the right and closer to the front seems to have the salads, fruits and vegetables, and some desserts. There is also an area where things like coffee and tea get put together.
Some food selections were 3 star items and some things were 4 star offerings. It was good, but it didn't rock my world. (That's probably because I keep trying to like Turkish food as much as I like Greek food.) I don't believe they had kunefe, which I really like, but they had something like baklava.
The interior is clean. It's on a major street close to the center, so there are big windows all around and the lighting is good. The service leaned amicable. The price is a good value and fair for this slightly more expensive country.
It's also easy to get here, being close to Helsinki's center. The Metro seems to weave across the city and surroundings in an east-west manner, so it won't get you close enough. However, one can easily hop on just one tram or bus and/or walk to reach this restaurant.
These latter observations kick up Istanbul Grilli to a solid 4 stars. In addition to that, the restaurant is popular and one will see customers who are locals, probable expats, tourists, and people of Turkish and Middle Eastern extraction. If such a diverse clientele frequents this eatery, that is also indicative that it's a worthwhile stop. read more