I love that they have been around since day one of my career! They always offer great customer service, are responsive to our needs as we grow/shrink teams or change products in house; their team is top notch - very knowledgeable about all things marketing automation (and more!).
Their pricing structure can be complicated at first glance but once you understand it's pretty straightforward with some upfront planning if needed so not too bad there either way really!! We use them primarily because its what everyone else uses which makes sense given how much demand exists within this space right now :) The only thing would like was an option where people could self host stack moo without having support from SMO when something goes wrong? But maybe thats just me wanting another choice haha :). Anyways other than those two issues everything has worked out well thus far though obviously happy customers helps keep us going forward ;).