Our on-ship Torgil experience was up to Viking's usual excellent standard: the crew was professional, capable, incredibly courteous and simply fun. The food was superb. We thoroughly enjoyed these folks. The Torgil is a bit older and smaller than the long ships, which means less common area. This would not necessarily be a problem, but for the rain that precluded full use of the top level.
The Douro River was beautiful -- beautiful vistas, cool locks -- and the opportunity to taste port, and more port, was everywhere, but that only goes so far for me. The Douro River experience was just not enough. We went three days up, three days down, and spent too much time on motor coaches to reach meaningful "in-port" experiences. There just wasn't enough to the river cruise part of this trip. For example, the Bread and WIne Museum, while very sweet, was tiny. Some of the spots were great, some were so-so.
We did the excellent Lisbon pre-cruise extension, to include the coastal city day trip (fabulous), all of which is a must-do. Lisbon is a wonderful city to visit, and four days there pre-cruise was not too much. We had a day and half in Porto, which was not enough. I would have liked more time there.