The only benefit I see with a mining rig is to be able to mine coins on credit card. Buying coins on credit card is insane now that visa MasterCard charging it as a cash advance. Plus coinbase had their own fees and we are still in a fall bear trend and have not reached winter accumulating season yet. Times will be slower for most of this year.

Buying a mining rig protects your capital investment from further coin price declines and as long as your breaking even with electricity cost your still paying cheaper than buying on coinbase.

Mining is an arms race fighting for left over pocket change someone dropped in the couch.  Profits are very slim to none after IRS gets their cut.