I can't help but thinking that under normal circumstances (your experience was different because of the lost bags) this must be the most inappropriate airport in the world to have such a service at.

Immigration queues at SIN are never an issue IME and bag retrieval is incredibly prompt, especially if you're in a front cabin.

Offer it at MIA, LHR or JFK when you arrive just after the CX flight, but otherwise it does seem rather indulgent (to me!)