An early stage lab has a lot in common with a startup. The PI is given seed money to validate an ambitious idea and has limited time and resources to do it. The work is extremely labor intensive and in the early stages the PI will be in the trenches with the early employees working in the lab and setting an example for them to follow. Fast failure and pivots are extremely common. Furthermore, at any time the research…
> An early stage lab has a lot in common with a startup. The problem is you also see this behavior in well established lab, where the PI has very little to lose if he quits research altogether. In my experience, the correlation with whether the professor was an assistant professor seeking tenure vs a well established full professor and the amount of work they make PhD students do is almost nil. It's mostly purely dri…
With an assistant prof you will be asked to do unreasonably long hours on ideas that haven't been fully validated, but you get a lot of face-time with the PI (for better or worse) and have a chance to get on the ground floor of a potentially great research program. Your boss has a lot more invested in your success because their career depends more on you. It can be exciting.
With a more established prof you are more likely be plugged into the n-th iteration of an established research program. You're more expendable because the prof has more options to hire your replacement; you can get lost in the crowd; the prof won't be in the lab as much (travel, service responsibilities) so it's more sink or swim. Lots can go wrong in this environment. As the group gets larger, internal politics can create frictions, especially if the supervisor is away a lot.
I see A) as better than B) but that is just me.