What is the best type of STP?

In the realm of cryptocurrency and finance, the question of "What is the best type of STP?" is a pertinent one, given the wide variety of Straight-Through Processing (STP) models available. STP, in essence, refers to the seamless and expedited transmission of orders from the client to the market, without any intermediary intervention or delay. When considering the "best" type of STP, one must evaluate factors such as efficiency, cost-effectiveness, and the ability to handle high volumes of transactions with minimal latency. Different STP solutions offer varying degrees of these advantages, and thus, the "best" STP depends on the specific needs and requirements of the financial institution or trading platform. Could you elaborate on the criteria you would use to determine the optimal STP solution?