Pros
As a small but powerful marketing strategy and technology consulting practice, I found the people and work creative, fun and hugely beneficial to our clients and to me as a consultant with many years experience. Acceleration brings some extraordinary talent and entrepreneurial flair to some of the leading marketers on the planet. Backed by WPP's Wunderman, enabled our teams to tap deep resource and open doors at the highest levels. I was impressed with the level of knowledge, experience and a unique balance of "drive" and care for work-life balance. Acceleration also has some outstanding leadership who are always ready to roll-up their sleeves and to pitch in, mentor and open doors to professional advancement.
Cons
Downsides are few ... being "smaller", there's always a tension in meeting a healthy level of demand with limited but exceptionally skilled resource (often, its a nice problem to have).