What sensor to use?

[Alex.q]

My team want to be able to detect when balls are in our collection system and at different points in it. We think we want to use a sensor like the one in garage doors that trip if there is an obstruction. I don't know a lot about electronics or sensors, so I am having a difficult time looking for a sensor that will fulfill this purpose and be relatively easy for our electronics and programming team to integrate into our system. Right now, I found the photo sensors on Andymark http://www.andymark.com/RightSight-p...-p/fc12-57.htm

Will this work or are there better options to suit my needs?

edit: these sensors look a lot like the line sensors last year, but I can't tell if they are the same. Are they?

Additionally, we will want to use a range finder to help target the basketball hoops with the shooter. I assume this would work best as a laser, but past that, I have no idea where to start looking for this. We could use the sonar sensor, but I'm not sure if this has enough range.