Pros
You will get paid slightly more than most other retail positions. You will get good discounts on gear if you are into the outdoors.
Cons
There is a reason that REI has fallen from the top ten of best companies to work for and is now in the bottom. I predict they will no longer be on the list in the coming years. With the hiring of a new CEO from Coach REI has decided to forget everything that made them a store people want to shop at. They are slowly becoming just another retail outlet, at present they have dropped many of their ideas such as "balance" for their employees. There are new availability requirements that mean you must work 16 hours per weekend. Which essentially means you must work an 8 hour shift on Saturday and open to close on Sunday. So much for balance. If you are someone who enjoys the outdoors and wants to have time to do those things, look elsewhere. If you are someone looking for a second job that they can work, look elsewhere. REI was my second job for a long time but they have started pushing out people like me with their new availability requirements and their new found inflexibility. If you want just another retail job, go for it. If you want to work somewhere that only cares about metrics that have very little to do with your actual job performance, go for it. If you want to work for a great company that values balance and is ready to be a great place to work then you'll want to find a time machine and go back about 6 years.