I won't think of staking high on this match because the last match between this two ended ridiculously, a draw. This guys are performing publicity stunts to gain popularity.
If I'm to bet on who would win, I will go for KSI because he fit aggressively and doesn't get weak easily. He knows about boxing, Logan only started practicing last year when they fixed a date for the fight.
There wasn't much ridiculous about the first draw, it was quite easy to see how Logan won rounds, 1,2 and 5, whereas KSI won the rest.
Since there was no knockdowns, it was obviously going to end in a draw.
In response to your comment on how long they've been boxing, Logan said he has been training at pretty much full intensity since their fight ended last year, KSI apparently only started training against a few months ago (after getting fat again).
In reality, they have probably both had similar amounts of training, but Logan is in better shape.