Thinglink & Voicethread . . . which to use?

The conundrum: a Spanish teacher wants her students to explore a piece of art and create a digital presentation. She'd like the presentation to include students speaking, links/videos to external sources, and the ability for students to work collaboratively.

Thinglink and Voicethread both allow for all of these, but they each have benefits and drawbacks.

Here's an example of a Voicethread (poor Dave Baroody is always my example):


The benefits I see: Voicethread's commenting process is simple, it's easy for groups to collaborate because Voicethread was built for conversations, students can draw on a picture as they speak to point viewers to details of paintings, and the groups could have more than one slide per presentation, so they could present more than one image. ALSO, because it's made for collaboration, there's also the possibility of sharing a Voicethread with a Spanish class from another school and connecting across schools.

The drawbacks: the comments are linked to a person rather than a part of the image, and so a person viewing the presentation doesn't know what the comments will be about until she's already pressed the comment. That makes the content of the presentation feel more about the conversation than it feels about the content.

The other option is Thinglink:
Benefits of Thinglink: It's pretty. Really pretty. And the comments are a part of the image, so it's very much a presentation tool, too. Students can collaborate by allowing each other to edit their image.

Drawbacks: Making a class as an educator seems like it would be frustrating. All links have to be external, so if a student wants to add a voice recording or a video, she has to know how to use Soundcloud or youtube respectively. The students can figure these things out quickly, but the number of steps means a larger likelihood of error, a larger digital footprint, and more class time devoted to negotiating the technical aspects of the program.

So, which would you use? I'm torn.