Have fun with it man, I love mine. You'll love it even more after you convert it. Check out saiga-12.com...some really knowledgeable guys over there when it comes to the S12's.
Are you sure thats a 25 round drum? It looks like a Mike D's and I thought those were 20's only. If you want a tri rail forend, I have a DPH for sale if you're interested.