I'd like to thank you all for your thoughts and advice! I wouldn't have even expected that you guys are gonna be so helpful. Once again, thanks a lot, it's very nice!
I'm on holidays now but when I'm back I'll make a setup then try with mids. If I find an old set of 45s strings I'll try them, otherwise I'll buy new ones and see what will happen.
Hope, I won't have to sell the Sandberg and buy a Stingray or a Fender
When it comes to Aguilar... I'm waiting for a message from Ben from Cardiff who's selling an AG500
So sorry for my English, I come from Poland, actually