Good, not the best - but looking at our current state of affairs - it really isn't bad. Consider the rest -
Jones - error prone and often injured; Rojo - when did he last play 5 games in a row for us? Bailley - has a future, but too error prone and rash; Lindelof - has a future, but not that good in air (the commanding CB every defence needs). I think Smalling is the best of the lot, a shit lot but still - better than the rest and consistent.
Those comparing to Vida, Rio need a reality check. One step at a time fellas.