In either case you will not have to worry about legitamacy!! Both products are well made and not conterfeited, at least so far. The question is do you want to use human grade gear or vet? Price wise you will save a considerable amount going with the Ttokkyo. Going price in TJ for the Ttokkyo is $24 for 5cc's, meaning about $4.80 per 250mg of sustanon. Where the redi-ject (again in TJ) are running between $8 - 12 per 250mg of sustanon. I for one have been very happy with the Ttokkyo products and have chosen to take the cheaper road, allowing my to buy more of other products. The results have been very good, I can't say I notice any difference between using the redi-jects and the ttokkyo. There was a time when the Ttokkyo caused excessive pain due to high BA content, but that problem has been fixed and the product hurts no more than any other sustanon.