Finishing up my sixth year - looking forward to many more with K12.
Pros
I have been with K12 for going on six years and am really quite happy. I make a little more money as a full time teacher here than I would if I were working at a local brick and mortar job doing the same work - except here I have such a flexible schedule. I teach four live sessions a week and have five one hour study halls. I set my own schedule. The benefits are outstanding. I get $50 a month in office supplies (that I get to choose and order from staples), I have wonderful insurances (I pay 1/3 of my health insurance - everything else is covered), I get $50 a month in Internet reimbursement, and I get a 5-10% bonus every year (depending on my performance and company profitability). My coworkers are amazing. I've made some lifelong friends here. I'm very grateful for my job.
Cons
I have to work through the summer since our school has year round enrollment. I hate that we don't get to meet our coworkers in person. Our retirement is a 401K with only a 3% match - much less than I would get in a public school.