Anyone using these spacers?

I think i'm going to order them, hit me back in a couple weeks and i'll let you know what i think of them. Looks like they'll work fine, hopefully the studs stock blaster studs dont break off or bend while landing hard. I like to brake during wheelies and go right into stoppies, a couple weeks of doing that will put them to the test! And i spend a lot of time sideways on 2 wheels. If they can be broke i'll break 'em.
 
i bought the 5" ones and had a problem with my tires hitting my nerfs so i sold em....they will hold up as long as your not doing 20 footers
 
i don't have nerfs so i should be fine. i'll be putting these on the rear so what size should i get so my front and rear tires stick out the same? btw i have a stock rear axle and my flipped fronts are coming in the mail lol
 
i have those exact ones and a set just like them that were made by a different company that you can use a ratchet to tighten. the one thing i hate about teh ones in the link is you need to use a wrench to tighten them and i cant get things as tight with a tiny wrench as i can a nice 1/2" drive ratchet and socket. they seem to hold up just fine tho.