My friend only needed 2 points for a 7 and got her exam remarked, and her grade actually increased! I don't know how many points she got, but she has a 7 now.
She had to pay 85 euros to get it remarked, but got her money back, as her grade was increased.
Not sure how long it took - we got our results in July 6, and I think she got her remark result by early-mid August.
In the end it went well for her, but I can't speak for everyone. If you missed a grade by only one or two points, and if you personally believed that you deserved better, I think you should go for it. Personally, I was just 4 points short for a 7, but my exam hadn't gone 'that' well and I didn't think my grade would actually increase, so I didn't get my paper remarked. So, it's kinda up to how you feel about your paper, really :)