@VanessaS they are smaller than campestratus indeed. Adult females can reach 14cm max. Although they tolerate low levels of humidity, when all mine were slings I kept them in high humidity and turned out well. They are really, REALLY, slow growers however, males tend to mature way faster than females so, I suggest you sexed them as soon as you can and, in case you have a couple, hold the male food a lil bit.
@Arachnid Addicted Both of mine are very tiny right now. They've moulted twice and might be 1/2". They are still moulting at the same time at the moment. I always try to sex them asap, just in case I end up with males and the seller still has others available. Thanks for the info!