Ventajas
Good Salary/Benefits, Clear Expectations, Low Drama. No cool-aid to drink, everybody has a family they love and want to get home to. This is work as work. Sure, some people have made it their whole life (and there are plenty of exciting opportunities) but there isn't the pressure that I found in start-ups to live and breath the company fervor and work crazy hours (though some people did) to prove your devotion. Personally I prefer the cut and dry straightforwardness of this steady and stalwart company. The company also had a great group mentality about projects--everybody got to go on tours of buildings, hear the exciting news at the monthly floor meetings, enjoy the perks of the exciting developments BxP vanguards. It was a fantastic company to be a part of--you felt (and could physically see!) the amazing building projects you were a part of.
Desventajas
Low tech (sometimes frustratingly so), not much mobility, often impersonal. The vacation/maternity leave policies are woefully outdated.