Which custom posts/fields plugin should I go for?

Which custom posts/fields plugin would yop recommend?

I would need to build a couple of websites, all of which share pretty much the same structure. Given the structure the one thing that I should implement is the ability to display posts given a certain characteristic (for instance students only). From what I’ve learned so far from working with WordPress, my best bet would be using custom posts/fields. So, I need some advice:

1) Which plugin should I go for? I need a plugin with a fairly good track record, meaning it won’t stop being updated any time soon (I know, nothing is certain, but I just need your general opinion which one seems to be the most reliable with respect to that.) The one that has the least problems.

2) The plugin should have widgets available or play nicely with some sort of custom search plugin which has a widget. Meaning, I would like to have widgets where a user can select what he wants to see (only teachers, only students…). If possible, it would be nice if I could add different widgets on different pages (on student pages a widget dealing only with students).

For instance, I would add age to both students and teachers, and on pages with students one might choose only teachers under 50. Or perhaps only show projects which are finished.

3) I’d prefer a free plugin, but paid ones are ok too.