I've been doing kettlebells since my marathon training started. I've got another month and a half left before my event (OMG, I can't believe it's just around the corner!!), so I'm planning on sticking to kettlebells till the end--except for the last two weeks, when they generally tell us to lay off on the lower body weights to conserve as much energy as we can for our lower body.
In previous years when I was training for half-marathons, I used both heavy weight/split routines and total body/endurance routines; I found both to be effective and just went with preference. This is my first full, so I didn't want to experiment too much. Because I figured the cardio/running portion of the training would be so demanding, I wanted to take it a little easier on my body in terms of weights, so rather than go for strength gains with heavy weight training, I decided to do more functional/lighter weight training.
So far so good!