Tool steel is tool steel, it's all in design, and in reloading dies the more complex simple designs are the best. Micro adjust sizer and seater are wonderful if you are looking to squeeze every bit of accuracy out of a gun, and if you have experience to use them properly.
This is an excellent statement and one which I basically agree. You can reload safe and accurate ammunition with any brand of die. I have Bonanza, Dillion, Lee, Lyman, RCBS, Redding dies, and they are all good. There are differences between the brands, for whatever reasons, Lee rifle dies seem to be cut larger and leave the case larger after sizing. This is of importance to me as my match ammunition has to function through several different rifles and in the end, I went looking for small base rifle dies. My Lyman small base dies sized the cases the most, and I use a Lyman small base die in the 30-06 and .223. Unfortunately Lyman stopped making small base dies and I don't have one of their small base dies in 308 Win. I am using an RCBS small base die in 308 Win. I would use small base dies in every caliber I could buy them.
I like a robust firing pin spindle/decapper. I stopped using Bonanza dies because of the propensity of busting the decapper. The Bonanza decapper is fragile. I gave away my 30-06 Bonanza sizing die to a friend for just this reason. I like the RCBS decapper, those are a robust design. The strongest decapper is the Lee. Older Lee decappers have a full length expansion section which makes pulling the case mouth through the decapper very difficult for long cases. I think Lee redesigned their decappers and made the expansion section shorter. With the exception of the Lee decapper, I have had the decapping pin come loose at one time or another with all brands.
I think Dillion dies are well thought out, the spring loaded decapper is an excellent idea and I do believe it works better on progressive presses than any other design. Overall Dillion dies work very well on progressive presses. Redding dies are hideously expensive, shiny and smooth, beautifully made, can't say the ammunition that comes out is any better.
I prefer the Micro adjuster rifle bullet seating dies for the convenience of adjustment. I measured a number of cases, measuring bullet run out, bullet run out for my .223 Lee dies is the same as the bullet run out with a Bonanza match seating die.
I do have one Lee sizing die in 30-06 that after sizing, the case run out is huge. I have experimented with the decapper, lock ring, lube thickness, I don't know why, but this die is a dud.
When it comes to pistol dies, I use Lee. They are cheap, work well on my Dillion 550B, the decapping pin stays put. I am using a Dillion 45 ACP sizing die for 45 ACP, I decided to splurge. I can't say my 45 ACP functions better or is more accurate due to the die change.