i think you always have the best chance to match at your home program and anywhere you do an away rotation - provided that you do a good job.
the previous comments are good ones. however, you also run the risk of being overbearing at your home program - skipping rounds on ob/gyn, medicine, neuro, etc to go to ortho conference at my home program will likely get the residents here thinking that you don't work hard where you are currently and may be a bad thing.
your home program is going to know you better than anyplace you interview for a day, for better or for worse. if your home program is big into numbers, your work ethic may not help as much unless you also have the numbers.
in my opinion, programs that match a lot of their own students probably value hard work very highly and select/rank those with a good track record which benefits hard working students from that program. also, a program that matches a lot of their own students can be a good thing b/c the students probably know the program better than outside applicants and probably rank that program highly, even though they know the dirt/downsides better.
that being said, i can add the disclaimer that my home program and my 2 aways are my top 3, so maybe i have some comfort factor bias