In terms of ease to use, I would rate it as quite poor because this is not an easy system at all when compared with other systems out there that are far more user friendly (and free).
You have little or no control over your data once you upload so in reality its just like having someone else look after everything for us - very unhelpful! There's also nothing wrong about any aspect but we've found ourselves unable too move forward from our current position using their services which means they're costing money without providing anything back either positive nor negative!! We used them mainly due to price however i think if one was willing/able then surely another supplier may be able do better than what timg did?