1- Use extreme caution, this is a volatile play, I think long term bound to make money but if you trade in and out of an ira (or reg trading account) and are not a professional you could lose money by buying selling at the wrong time. I used like 5% of my ira to buy.
2- I dont know all the rules but w my 401k, cant buy any stocks, only etfs and funds. My ira I can buy individual stocks. Sometimes you just get the wrong guy on the phone.