This is the first time I can recall someone on this forum giving me the benefit of a doubt when I made an error. Thanks.
I pulled the dies out on the SD to double check. I stand corrected. They are carbide.
While I was at it I even put in primers and powder. It does make ammo. The powder measure is basicly the same as the one on the 550b. That powder measure works well. I loaded 50 rounds of .45 apc and the oal is just as consistant as the 550b. I'm not able to see if the primer has fed like I can on the 550b. It does take more effort to load with the SD than the 550b. I have the orginal round ball handle on both. I don't see any real reason to switch to the other handle Dillon makes for pistol ammo on the 550. I can see where that handle will help on the SD press. I also suggest the strong mount for the SD.
There are differences between the presses Dillon makes. You don't get much speed advantage with the 650 over the 550b unless you add the case feeder. Now, there is even a case feeder for the 550b. I haven't heard much about how that is working out. I think I have a little more control with the 550b operation since it only advances when I want it to. Being able to advance slowly when loading ammo the is close to a compressed load means I don't spill powder all over the place. It also makes adjusting the powder measure easier to do in my opinion.
There is a version of the 550 which is more like a turret and you can add parts to it until it becomes a full RL 550b. I'm not sure how much extra you might pay doing that way.
I have loaded well over 30k on my RL 550b over the past 12 months and probably will load close to that amount over the next 12 month. My experience with the SDB to date is limited to 50 rounds and several months just sitting on the bench waiting to get used. I'll leave it set up to load .45 large primers as I orginally planned to do with it. Yes, both of these presses have the no B.S. warrenty and that is worth a lot. A quick call and parts if needed are on the way. It takes a couple days longer if you just send an E-mail.