I’ve tasted a great bunch of Finnish fruit wines over the years. Most of them have been subpar in quality - and that’s putting it nicely. I’ve heard several people say that the main culprit in this might be the “winemaking school” they have at Lepaa, Finland, where they teach how to make alcoholic beverages, but when it comes to fruit wines, the methods are not that applicable to quality fruit wine. And unfortunately almost all the people who run wineries in Finland are either self-taught or they’ve done their studies at the Lepaa “winemaking school”.
Basically the only exception to the miserable level of quality in the Finnish fruit wine scene is Ainoa - their wines are actually world-class. That might not be much when it comes to wines, but it’s huge when it comes to fruit wines. Their wines are not only drinkable, they’re actually good! The irony here is that the winery is not run by Finnish people, but instead an American-Ecuadorian couple. But I guess it takes foreigners to teach us how to make good stuff, because we have world-class berries here - only no know-how how to turn them into great wines. As the fine people at Ainoa have never gone to the Lepaa winemaking school, they are not repeating the mistakes taught there.
When it comes to obtaining these bottles, you must be aware that we have alcohol monopoly system here in Finland, meaning that you can buy anything above 5,5% ABV only from monopoly stores. Fortunately there’s dozens of these stores in Helsinki.
You can check out the store locations from https://www.alko.fi/en/ → Stores (or just search Google Maps for “Alko”). However, most of these stores don’t carry any Ainoa wines.
The selection of Ainoa wines available in Alko is here: https://www.alko.fi/en/products/paging?SearchTerm=Ainoa
You can also check out where each wine is available from the product availability / store locator dropdown menu. Probably the best selection of Ainoa wines is in the flagship store in the middle of Helsinki center, Alko Arkadia; they have five different wines.
If you have time and means, you can also visit the Ainoa winery - they are located about an hour’s drive away from Helsinki. However, you really need a car to get there - the winery is pretty much in the middle of nowhere.
As for the other producers, Hermanni makes somewhat decent wines, but they are ultimately pretty meh - nothing special to write home about. Teiskon viini is a big nope for me.
If you’re really interested, here’s the whole selection of Finnish fruit wines available in Alko. Apart from the Ainoa wines and the ciders/apple wines made by Kuura or Brinkhall’s, most of them are pretty much garbage.