Thumbs up is really not much to look at. If you are looking for somewhere just slightly more appealing head over to Tofu Village (http://www.yelp.ca/biz/tofu-village-house-of-soon-tofu-toronto), but the ambiance is really not what pulls one to Koreatown anyway.
Thumbs Up has awesome service. The guy that was waiting the day I ventured in was overly friendly and extremely attentive. I ordered a totally custom creation with tofu, veggies and lots of spice. He was really nice in going back and forth, letting me know what could work and what couldn't. Considering that everything is so cheap, he really went above and beyond what I expect.
The banchan were pretty decent as well, so I'd be back in a heartbeat.