The 500 I had with the 8" barrel was a pussycat with 325grain jhp. The massive weight really mitigated any recoil. Now a 500 with those 4" barrels I wouldn"t want any part of. I never did try the 400g "grizzly rounds" though, I would bet they would have jumped my 500.
The M29 was 100x worse with 44 mags than the 500 with 500mag rounds. Of course they have 500 specials now but they are still incredibly expensive, over $30 for 20rds. Where as 50 rds of 44 specials at the gun show for $21.00 and shot like .38s.
The 500 was a great gun but you really need deep pockets to feed it. Even reloading, the components are high for that.