I've only seen from the 9th Doctors and onward but I've enjoyed that show very very much! From what I've noticed people like Tennants character the best and as much as I 'love' his character I actually like Matt Smiths more. He seems less troubled by his loss/actions than Tennant but it's those times where he shows his age and.. tiredness (?) that draw me to his character because it contrasts from his norm; mostly he is quirky and more interested/fascinated, also a good thing.