Unless you're hitting huge features, you shouldn't need anything higher than a 12 din, you probably would be fine on entry level binders, due to the fact you're only 115. Out of interest, what DIN do you ride on, nobody on here will want to tell you what to ride on, so if you say what you ride on that will help us decide wether you even need a 12 din. If you ride a sensible din for your weight/height/ability level, the only real reason why you'd buy a 12 din binding is for the added durability over entry level bindings such as a marker free ten.
I can't give any opinions on entry level bindings, however I can comment on some 12 din bindings which I have used when I was lighter. My favorite 12 din binding is probably the Rossi Axial2 120/Look PX12, see my review here -http://aslansskiblog.blogspot.co.uk/2012/08/rossignol-axial2-120-ski-binding-review.html
if you've got any questions on the review or the above, feel free to pm me or comment on the blog. Hope this helps, Joey