Your first consideration should normally be price and if these miles will help you maintain status, as well as flight duration and times. I fly TAP regularly in J because it has the cheapest J fares and also helps me qualify for *A Gold. TAP has a very bad reputation for refunds (takes up to 2 years), so only book if quite certain you will fly it. KLM probably has slightly better J experience and perhaps slightly more reliable as an airline overall.

In your case, because of the direct flights, and both legs in J, and if same price I will go hands down with TAP. But if KLM is at least $300 cheaper and you need the ST miles, then go with KLM. Transit in AMS also has some risk.