I ended up losing 3 out of the 6. Two of them were in very poor condition when they arrived. I actually thought they were DOA, but they were barely hanging on. I was able to bring them both back to the point that they could stand and walk around, and one even started to eat and drink, but one never wanted to eat or drink on its own, despite my continuous all day efforts to nurse it back it passed that night. Then the other one took a turn for the worst the next morning and I couldn't bring it back. That one died the next afternoon, and then the one that actually seemed to be the strongest when they arrived took a strange turn overnight the first night as well and was lethargic the next day, I tried my best with that one too. Syringe feeding water with Electrolytes, and sugar water. Scrambled egg mixtures, mashed up warm chick started, but for some reason that one passed too. I had no idea why because it was absolutely fine the day before. I held it while it passed :,(
Two of my remaining three have had issues with pasty butt on and off from the start but I've been able to keep it under control. They both seemed a little lethargic this morning and I got really scared I'd lose them too, but I did more water with electrolytes, cleaned their bootys and made up some mash with their food and by the afternoon today all three were doing well. Finally acting like normal chicks. Running around, eating a ton, drinking, and taking quick snoozes before running again.

Other than checking their butts quite often I've finally begun to relax. I really hope I don't have to go through losing any others!
Anymore advice on how to get them over the pasty butt? One in particular keeps having issues with it.
They are so dang cute, but I don't know if I'd ever go through the shipping process again. Too dang stressful and it just breaks my heart to lose any of them that way. I knew it was a possibility to have losses but was really hoping they'd all make it.

I never knew how emotionally/physically/mentally exhausting it could be to try and nurse 6 chicks back from a stressful trip. Don't want to go through that again. Ever.
Again I'm really not trying to give MPC a bad review! Their customer service has been great through the whole process, and they're refunding me for the three chicks that passed. I just did not have a good experience with the shipping process, and because of that I will probably not order again.
So I guess my advice to everyone out their trying to decide wether or not to use MPC (or any hatchery) is this: MPC does their best to keep their chicks warm and cozy on their journey. My box had lots of hay and two heat packs. The chicks were adorable and a nice variety for an assortment of silkie bantams. I had one with a curled toe, but other than that no weird birth defects. My advice would be if you're going to go with a hatchery I think MPC is great, but do prepare yourself for possibly very stressed chicks if the delivery doesn't go well or takes longer than it should or the weather is very cold. You think you'll be the lucky one to get all perfectly rambunctious happy chicks, you never think you'll be the one to end up with all chicks stressed and barely moving, but it can happen! So be prepared to handle it and possibly having to spend all day and all night with those chickies for however long they need it! It can be an extremely tough situation to go through. I can say that I have learned a lot! But wouldn't want to do it again any time soon!
There's my long post!
I adore my three chickies and I'm glad to hopefully be past the worst of it!!