I'd venture in saying that if recruiters have any kind of idea of what it is to build a startup, they'll consider it a major plus. That being said, and considering what you usually see from recruiters, I'd say they'd have to be in a startup to know...
At a startup you're put into a situation where you are under major pressure and you're constantly faced with tough/unsolved problems and or all imaginable difficulties when it comes to sales. This can be an amazing growth experience, depending on how you deal with it. 7 months into my startup, I find that I've grown by leaps and bounds when compared to my former jobs, where I was already quite entrepreneurial.
As to an eventual stigma in the UK, it's only worse in other EU countries; I know it is in mine. Here, people are more valued for obedience rather than for entrepreneurial attitude.
At a startup you're put into a situation where you are under major pressure and you're constantly faced with tough/unsolved problems and or all imaginable difficulties when it comes to sales. This can be an amazing growth experience, depending on how you deal with it. 7 months into my startup, I find that I've grown by leaps and bounds when compared to my former jobs, where I was already quite entrepreneurial.
As to an eventual stigma in the UK, it's only worse in other EU countries; I know it is in mine. Here, people are more valued for obedience rather than for entrepreneurial attitude.