I went ahead and pulled the trigger on the factory Thumbhole stock for the SP-10 3 years ago. Yes, it was expensive, but it made all the difference in the world to me. It feels like a different, more stable shotgun. The stock is wood and weighs more than the synthetic stock. It really shifts the weight/balance point more to the rear and it helps off-set the muzzle-heavy feel when I'm shooting my 30" barrel. It IS a heavy shotgun for sure.