For me, Gaba was great. I was working part time at a university and also freelance with several other companies. However, I still ended up having a lot of "dead" space in my schedule. I wanted a place that was flexible with hours, and really there is no better place when it comes to that. I booked only the times I wanted to and was able to make a nice side income. As an unexpected bonus, my LS was in a very suave location and outfitted appropriately. It was a more pleasant working conditions than a lot of Tokyo eikaiwas. I'd say that Gaba suits you if you consider yourself more of a professional, and definitely personally motivated.