Angus is litter trained (well, mostly
) and we love it. When he needs to go, he just runs over to his box and goes, all on his own (but we keep a close eye on him to be sure he's consistent...he's almost 19 weeks old). I feel good knowing that he never has to hold it if he needs to go (I don't, so I figure why should he?). This is by no means a solution for everyone, but for our lifestyle, it really works for us.
We use Yesterday's News dog litter. I can't say that I love it, so I'm researching other options. Until recently (like this week) Angus kept eating it (eeesh...
) so there was lots of work to keep him from swallowing it.
It might take longer to litter train (I have no idea...I've never houstrained a puppy before, so I have no basis for comparison), but I figure I'm going to pick up poop anyway, so it might as well be inside...and flush...than outside, especially when it's miserably cold or raining.