I have found out that some of the smaller schools that have nearby medschools or research projects right within the school can provide some of the best opportunities for research since the large campuses usually have a lot of premeds vying for whatever research positions are available and this brings down the quality of the experience. You are sometimes given a free reign when the conditions are right. I work with a sub-PI and a PI simultaneously and after half a year of getting started I was basically given access to all the equipment to run the experiment by myself, with no one there. This gave me the spot for first authorship, but it was hard work. Not only training alone took some months, but the experiment had to be run continuously and every day (for about a week + weekends) I had to go to the lab after school and sometimes stay there until 2AM until I could finish up. After all that, data analysis begins...
Your experience will vary depending on what research you do and who's your PI. For example, brain research is very time consuming because of the delicacies and the amount of equipment and physics involved, but all that matters is that you like whatever you do. So choose something you like or you will either not learn anything or not get any publications (or both). If you don't like research at all, your ability to get a good recommendation at the end will be jeopardized as well. No good PI is going to give you a letter unless you put in the time.