The moral of the story of this trip is that the usual stomping grounds in Ximending's Wan Nian building are better. While this place was certainly impressive, their selection is not nearly so good (especially of Master Grade kits) and their prices are considerably higher. (The MG Gouf custom, for instance, was priced at NT$1300 — about $40 US — while at Ximen it goes for around NT$750 — ~$23 US.) While there was more gallery space there, a good many of the models weren't nearly as good as those to be seen in the Wan Nian building. I suppose Gundam Base does have three giant gundams standing guard, but then again I've seen the 1/12 RX-78-2 and Char's Zaku II hanging out in the middle of Ximending before.
Additionally, Gundam Base doesn't appear to have any paints or other modeling supplies. They do have every Gundam show ever on DVD (in Chinese), but then again I'm sure Wan Nian building does too, if I poked my head in one of the not-Gunpla shops. (Besides, what's the internet for?)
Ultimately, I'm glad to have checked the place out, but Ximen will remain the place to go.