I have all of mine in a Roth IRA, so tax-free earnings if I wait until I'm older. Actually, it's in my wife's account, who is 3 1/2 years older than me, so it's all tax-free once I'm 56! :-)
Most OTCbb or OTC are not a good idea for an IRA as they can change fast. Now with that said an IRA should be intended for long term and when you do find one this good of a business plan then it is a good idea to add there.
Not all but most IRA charge higher fees and to recover the fees on a trade the price needs to increase in proportion to the cost to recover the fee. Now for long term ones more then a six month to a year then the cost to buy and sell are not much of a consideration also.
In my opinion and IRA is for retirement and you need to keep an equal mix of aggressive to small growth in it for that purpose. With your age that varies also but as I told another driver today in his sixties his mix might be lower on the aggressive now. Younger folks go as high as 75% or more.
A good plan I use is my short term money I might need for the next six months I get a little more aggressive but my retirement is getting less chancy then ten years ago but heck I am almost as old as Charles. Almost old as dirt. lol
If this helps great but is not a recommendation for all portfolios and styles of trading.