A solid solid four.
Sid was the most adorable ghost I've ever read about (which unfortunately isn't many. . . But still!). I loved Sid and his whole awkward manner and low self esteem. He was like a gigantic cuddly bear who you want to pat 24/7 just because you can. And Alex was pretty unremarkable as a character but still very likeable. Nothing really stood out about him though. He was still very cute when he was despairing over Sid though, which, in actuality, probably just links back to my love to Sid.
The story line was unique yet not at the same time if that makes sense. I actually read a book similar to this at all, with the whole ghost fiasco, but if you actually look at what occurs in the book it's pretty predictable and anyone could have easily thought up this idea. Or maybe because I read a spoiler beforehand so I knew what would happen. . . Sigh I hate my spoiler tag reading habits.
Anyway overall I adored this story, and the mini side thing going on with the secondary characters (major LOL), and I would definitely recommend it to any who enjoy this genre. It's a fun read.
Oh and I hated the ending. Well not hated in the sense that I would say that the story was better off without it, it was more of a "WHY IS LIFE SO UNFAIR". The sort of hate where you come aggravated and started rewriting the ending in your head where all is well and rainbows and unicorns and fluffy candy floss clouds.