PS Audio 200C X vs. 200Delta?

I got a PS Audio 200Delta Power Amp in package buy from a dealer, and I can't find the info I'm looking for anywhere. Which is: Which came first? How are they related design and buildwise? And of course how do they compare soundwise? Anybody familiar with both of them?
167c2f8c b422 4e59 92cf 53226ac55842bdp24
Old Post 3+ years old and just ran across it. I knew the info, so I'm updating the post...
The 200C/200Cx is the last amps that were put out under Paul McGowan's watch.  He had Bob Odell do this amp.  It is 200 to 8, 400 to 4 and 800 to 2 ohms,  came out in 1985 and was considered a revelation for the money, being held in high regard.  It is a Stereophile Class A rated amp and The reviews that I have read both say,  you need to compare this to any amplifier at any price before you buy.  The Delta 200,  came shortly after that, after Randy Patton bought the company.  He had Greg Shug do that amp.  I believe that the 200C is a better sounding amp overall, but the Delta 200 is no slouch.  The 200C is much more temperamental,  anything plugged or unplugged from this amp must be done with the amp turned off or it is possible to short it out, plus it has a Magnacraft turn on relay coil that can get quite noisy.  The Delta has no such issues. On the used market these are both huge values... Especially the 200C.  It is a sweet sounding amp and goes very inexpensively. 
Thanks Tim. When I posed the question, the amp had been packed away for a few years, and my memory of it was faulty. Mine is actually the "C" version, and pretty impressive for what they go for/what I paid for it. A much better amp than the Adcom 555 (of which I had a few, and consider over-rated, especially by Anthony Cordesman in his Stereophile review, as he commonly does), which sells for about the same now.
Not a problem Eric, I thought that you might not need it anymore, but it could answer for someone else at another time... by the way, I did not mention,  If I remember correctly, I sold Delta 200's in my own store in 1991.
the 200C and Cx ran the rails right at the voltage limits of the caps, so worked the caps pretty hard. May be in need of a recap.
Both versions did offer lots of power...
I've had too many amps come through my hands over the past couple of years.  I have a 200C now. Hence me looking around and finding this post.  I haven't measured rail voltage, but I did check the caps.  They all measure around 16,500 mfd each and are 75volt parts, no signs of leaking.  I may replace them soon,  but they sure look good. I've been considering replacing a few of the small electrolytic on the boards.  I figure that I'll replace filter caps at that time. I'm a speaker guy and don't claim to know much about amps,  but I'm thinking "why not" on some parts changes.  This amp already sounds WAAAAY above its price point. 
I agree, Tim. A 200C can be had for $400-$500! The thing weighs a ton, with a massive transformer and power supply. Built like a battleship, as they say. I use it on my Magneplanar Tympani and Eminent Technology LFT-4 bass panels. 200w/ch at 8 ohms, 400 at 4.