I only had two days in Bariloche and felt like I had to go to Butterfly given the reviews, even though it was an hour drive from my hotel (my taxi driver was a happy man!).
Based on my global gastronomic experience (which includes michelin and non-michelin), I will rate Butterfly as good overall.
I appreciate the fact that they create their menus based on the fresh ingredients available daily, and hence the concept of the surprise menu. And they are very accommodating with dietary requirements.
The first few courses were nice and then when I was told that the main would be a lamb dish, I started to worry because I really don't like lamb unless it's perfectly cooked (so you don't get that weird lamb taste). Even before the dish arrived, I was already trying to find excuses for not finishing that dish. But omg, it was the best lamb dish ever! At that point, my rating for Butterfly was sky high. Then, came the desserts and petits fours... I have a sweet tooth, and I found them disappointing.
I'm not sure if it's the best restaurant in Bariloche, as I only been to two there. The other one was much more casual and everything faultless.
Oh and service was very good.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.