- I wanted a working prototype built quickly, so for now the UI isn't as important.
- If I did decide to stick with the framework, I knew that the site wouldn't be consumer-facing, and there'd be no benefit to using the site on a mobile as it's basically a CMS.
So I got to work, and as a framework for building the frontends of web apps, it's pretty brilliant. With the absolute minimum of custom-written CSS, I have a beautiful and super-functional app. All the stuff you'd think of has been considered: forms, buttons, pagination, even modal dialogue boxes, breadcrumb trails, alert messages... it's all there. And it looks lovely.
If I were building something consumer-facing, I might shy away from it, or add so much of my own styling (to cover its origins) as to negate the time I'd saved in using it. But as what I'm building is essentially a CMS, it's the best framework I've used.
It's not an everyday case, and the issues I mentioned in that post still stand: it's got a degree of flexibility but isn't what you'd call responsive, but it's let me build something attractive and functional, quickly.
So, in answer to the question "do we need another grid framework?" No, but now and again it's bloody useful to have one.