Vantaggi
It's a great time to be in tech. I'm not one to drink the kool-aid, but we really have an awesome product and are growing like crazy. It's a fun company. it's cheesy to say, but the culture is great. I can walk in any door with a question and the worst answer I'll get is "I'm not sure, try asking ____". Overall though, it's enjoyable being here and helping the company grow, as well as having my career grow along with it.
Svantaggi
The biggest downside is that there is not always a well defined career path. So you may not know what the next step is going to be. In a fast growing company that's not entirely bad though, as new positions are created to fit the needs of the business, I'm in one now. But, I didn't know that it was an option until it was.