To add something, all Tarantulas/Scorpions/Centipedes(not millipedes) are venomous, and you can't remove their venom, like some people I talk to always tell me: Why don't you remove the venom of your T/Scorps?!?! lol... I don't know where they took that urban legend from...
Good luck w/ your first scorp, with H. spadix/arizonensis you'll have a very active scorp, often stinging its preys, and not that dangerous, some people says that their Hardrurus arizonensis are more agressive than their hot scorps! On my side, my h. arizonensis died 2 weeks ago... It was very active, I really like that specie, if ever I get money, I could do a big tank with some h. arizonensis, as they are communal... if I could find someone who's breeding them... (I don't like WC)
As for scorpions all being venomous, well, yes, but I have one H. arizonensis who lacks the ability to inject venom (no telson), and he has survived quite well. He lives alongside four others and eats as much as the male (same species) in the other enclosure, so I know he is fine. I'm not exactly sure how he lost it, but he was an addition that was included in a previous order from a guy who I purchased his entire collection. I still don't handle him, but at least I could and not get stung.
Frank...I seriously doubt you will find anyone who is breeding them as no one has sucessfully reared a Hadrurus from birth to adult...it is suspected the conditions are very specific and difficult to maintain. The furthest I have heard anyone sucessfully rearing them is to 3rd instar. Atavuss may be on the verge of getting some to make it to 4th instar but last I heard has not as of yet. They are nearing that stage from his last comments.
As for buying juvies...I doubt you will find ones that were born captive other than those younger than 3rd instar, I which case thay will most likely not make it much further. Other juvies you will find on the market will most likely be sub-adults at best and they will certainly be WC.