I've loaded with a lot of Rainier, Berry's, and Extreme plated bullets and can tell you their plating is a LOT tougher than most are aware of. Now, please read the following carefully, because I have seen so many replies by people reading what they expected rather that actually reading what I posted.
Anytime I load a new to me bullet or use a new to me setup I assemble some dummy rounds and pull the bullet to check for issues. Using a combined combined Seat/Crimp setup in 38 special and 45 ACP with a plated bullet I have had no issues with damaged plating when checked using a 20X magnifier. However, with Speer Gold Dots and Hornady XTP bullets I've seen a raised ring of jacketing pushed up in front of the casing and that ring is sharp enough on the pulled bullets you could cut yourself on it.
Now, read that again carefully. Plated bullets crimped with a completely normal crimp (both roll and taper) using a combined Seat/Crimp had no visible damage to the plating under 20X magnification. Expensive Hunting or SD Jacketed bullets had a large ring of jacketing pushed up using a combined Seat/Crimp setup. This is the opposite of what most seem to expect and I am fairly certain someone will post that "plated bullets need special handling" or something to that effect.
Fact is that plated bullets from any of the major brands do not need any special handling in regards to crimping whatsoever. About the only suggested limitation is that the velocity be kept below 1200 fps for the standard plate and 1500 fps for the heavy plate bullets. Note, Berry's and Extreme now both offer Heavy Plate bullets in some weights and calibers and I've found Extreme's 165 gn. heavy plate HP's work very very well in a 1150 fps load I use as a practice equivalent for my carry load, a 1150 fps Gold Dot.
Addendum. Someone will inevitably post what is recommended on the bullets suppliers web site and I will note that most recommend a light crimp. However, I am reporting REAL WORLD RESULTS here, not what my corporate lawyer told me I should post. The simple fact is that the plated bullets from a good brand are very tough and can be treated rather harshly. Anyone who want to double check this is free to load up a dummy round and pull the bullet and look at it. If you take the time to do that you will be surprised to find that you can use enough crimp to cause the case to buckle and won't see any visible damage.
Second addendum. Cases buckling in the revolver caliber is probably the biggest issue I've seen with a combined Seat/Crimp operation. I now separate the seating and crimping with all of my 357 Magnum loads due to problems with buckled cases. So, pay attention to that potential problem and plan for it if you find it's a problem. Because a badly buckled case will NOT fit in a revolver cylinder no matter how hard you push.