I much preferred Tobey Maguire, perhaps because I really didn't like TASM or its sequel. TASM never endeared itself to me so I didn't get attached to anything in it. The Raimi films did and I love them, might have something to do with my age when watching them, I was a kid when the Raimi films came out and grown up for TASM, but I still love the Raimi films.
Maguire's Peter Parker got the nerdy loser thing down just right. He's not cool or charismatic, people walk over him because he's got quite a passive personality but he finds his own ways to shine. He can be nice and impress people (like Norman Osborn/Otto Octavius) but that's mostly down to his cleverness and endearing nature. I especially liked the bits where Peter and Otto get to talk in Spider-Man 2 before everything goes bad.
Garfield's Peter Parker is really quite awful in my opinion. He's FAR too cool to be Peter Parker, I know some versions of PP have him being more of a hip teenager and less of a high-school loser but I like PP to be a loser in his average life, contrasts better with being Spider-Man. He cracks wise (out of costume, it's fine when he's in costume), he's scooting around on that skateboard and everything about the way he looks screams hipster. Peter Parker is not a hipster.
Maguire's Spider-Man does cool stuff, looks the part, and was exactly what kid me thought Spider Man should be. More than that though, the way he differs from portraying PP and SM is huge. Maguire's Spider-Man is an escape to being somebody else for Peter Parker, Spider-Man is confident, cool, and generally awesome in the ways that Peter Parker never can be. Something I have also come to realise and appreciate is that apart from the voice (that he makes no effort to disguise), you'd not really suspect Peter Parker of being Spider-Man because of how they act differently. It reminds me of one of the many reasons I really liked Michael Keaton as Bruce Wayne/Batman, because you'd never suspect it was him under the mask if you didn't already know. The mask and face under it are two very different people.
Garfield's Spider-Man never burst out at me as a much more superior portrayal is it did to many others. He cracks wise as Spider-Man should, but he already did that anyway as Peter Parker, plus there's some meanness to him at the start when he's giving the cop crap. Didn't like that. There didn't seem to be much change between Peter Parker and Spider-Man, I saw Garfield's Parker and thought "Your're such an annoying hipster prat." Saw his Spider-Man and though exactly the same.