The problem with the SDB is that there is no future growth with that device. It works great, but you have to use special Dillon dies. If you want a Lee factory crimp die, (which is one of the better crimping systems out there), you can't use it. It doesn't fit in a SDB.How about the dillon square deal b?
I have had a Dillon 450 for 35+ years. It's the 550 now. I have made the upgrades to the 550 except for the tool head which is nice. I keep about a thousand of each caliber (many) on hand and this model suits me fine. I do not need to do 500 an hour since 5.56 and a Thompson are not in the stable. The Dillon dies are great and I use RCBS as well. The Dillon folks are great to deal with if and when you need them.