We've been working with them for several years now so we know they're reliable! They have always met our expectations when it comes down to creating new content or making changes in existing ones; not only that but I'd say 99% of my clients are very happy as well - which is saying something considering how many people out there offer this service :).
Not much at all really... sometimes you need an extra hand helping get things done (or maybe just reminding me about deadlines!) Other than those two small issues above everything else has gone smoothly since day 1 :) Very friendly team who are always willing to go that extra mile for you. We have recently started using them as part of our agency partnership with F2M which is fantastic! Nothing at this point! They were great when we used them in house but they also helped us transition into an agency partner relationship so I can't fault too much from before then!