I love the wood grips from Ahrends. On my 629s, however, it forces them into .44 Russian & Special levels, only. For real Magnums, the Hogue made for S&W X-frame monogrip, as delivered on the .460/.500 Magnum S&Ws, is quite an improvement. It covers the backstrap with an absorptive material, effectively converting the sharp snap recoil to a push. The muzzle rise from the lite barrel/lug is still there - but acceptable. My 4" regular 629, which only weighs 2 oz more than the 629MG, is shown in my first page post. I first tried it on my earlier 629MG, where it made the UMC 180gr SJHPs shootable. I think the grips, only available via S&W Accessories, are ~$37 + s/h. They add ~#/16 in to the trigger reach.
Stainz