I recently bought a Diana mini on impulse, and I was very hesitant to use it because manual cameras were never a good experience.
I'm very happy with how these turned out. I might have half-assed it because I didn't want to feel sad about good pictures not turning out well. It also gave me a chance to go crazy with the options and note how they effect the photographs. What I mostly love about the Diana is it's low-fi-dreamy square photos. They have a nice journaling feel to them.