Well... I`m not quite sure what brand exactly, but I`m using some kind of Czech-made 100-45's that are sold in a local store. Their cheap, they last decently enough for the price (10 eu) and are really good for playing heavy metal (these strings have this nice warm sound), like Iron Maiden and Accept. But when i want to do something more jazzy/funky i put on some DARCO`s 95-40's and I`m on my way