Does it help to have been in 2 or more labs simultaneously?

[Quicksand]

If someone had worked in two, or even three labs, for several years as an undergrad, does that make any discernible difference in one's chances of admittance to a good doctorate program? Is the value added not too significant, compared to having worked in one lab for the same period of time? Is there going to be a significant increase between one's odds of admittance when going from two labs, to three labs? Just curious how much the overall time spent conducting research impacts admissions, and whether universities might just view this as meaning that I didn't work too hard in any of the labs. Thanks!

[twocosmicfish]

In general, working in multiple labs is a benefit during admissions provided you have glowing LOR's from them all. However, it is far better to have a single long research experience than to have several short ones. The longer experience provides a better relationship with the PI, and gives you the possibility of presentations and publications.