Hell bent for leather

I really want some leather shorts. REALLY REALLY want some!  Now my chase is on to find the perfect pair and I’m very torn at the moment.
Firstly, I think I need to try some on.  I’m not the smallest of girls and I don’t really want to to waste money on something that makes me look like an elephant! Secondly, I need to work out how much to spend on them.  From my hunt so far I have found the very cheap-
Faux leather from Boohoo

http://www.boohoo.com/shorts-and-playsuits/claire-faux-leather-shorts/invt/azz77760?_lm_esp=14-92-645
Faux leather from Asos

http://www.asos.com/Vero-Moda/Vero-Moda-Faux-Leather-Shorts/Prod/pgeproduct.aspx?iid=1396384&SearchQuery=leather%20shorts&sh=0&pge=0&pgesize=20&sort=-1&clr=Black
Real leather from Asos

http://www.asos.com/Vero-Moda-Very/Vero-Moda-Very-Leather-Shorts/Prod/pgeproduct.aspx?iid=1384245&SearchQuery=leather%20shorts&sh=0&pge=0&pgesize=20&sort=3&clr=Black
Real leather from Topshop

http://www.topshop.com/webapp/wcs/stores/servlet/ProductDisplay?beginIndex=0&viewAllFlag=&catalogId=33057&storeId=12556&productId=2060836&langId=-1&categoryId=&searchTerm=leather%20shorts&pageSize=20
To be honest I’m leaning towards the more expensive.  The Boohoo ones look way too short for me and there’s not much difference price wise, in the real and faux leather from ASOS, although style-wise I’m actually favouring the ASOS faux leather.  It would be lovely to hear your thoughts.
I am struggling with size though.  Do I buy my normal size or buy them a size too big to eliminate the hoochy risk? I just don’t know!  Are there any leather shorts wearers out there that can help?

Edit: I went for the faux leather asos pair as they were my favourite style. Look out for a post when they arrive.