If your choosing between the B unit, and a used unit, get the B stock. For the warranty at least. I almost bought that same unit last week but instead went for a second-hand unit from a user. Worst purchasing decision I have ever made. I only saved £60 over the B-Stock price, I stupidly wanted the box which the B stock didn’t have. Within hours I found it had the headphone crackle/dropout problem and a bent pin in the CF reader. But no warranty means I’m stuck.