Sometimes 'was' sounds awkward because so many people use was in everyday conversation without really thinking. I always teach my students 'were' though because it helps them to recognise that the sentence is conditional (as you'd never use 'were' otherwise). I think were becomes more natural sounding the more you use it. For example, after a year of teaching, I find myself cringing slightly when I hear someone use 'was' (maybe that's just my teacher brain speaking though).
I think in everyday conversation, no one would really judge you for using 'was' (except for a pernickety TEFL teacher haha!)
Hopefully this article might help youhttp://saritaagerman.blogspot.it/2012/1 ... onals.html