as with software development, people will benefit the most by working with the most experienced, capable, and intelligent teams that they can join. junior and senior is fairly meaningless, it is all about what knowledge, technique, and resources are available for long-term exposure as a motivated 'student' will be able to gain the most from that and achieve greater success for themselves and their organization. I recommend also looking for clues as to how much friction (impediments) there is in how people go about their work on a daily basis.