I'm heavily invested in 5.45 so it only makes sense to get a 5.45 upper.  I'm leaning towards the Huldra but I have a few questions.

1. Cleaning. How easy are they to clean after shooting corrosive ammo?

2. Reliability. Overall, how reliable are these uppers?

I know that DI is a proven system but i also primarily shoot 7N6 so there is a question about dumping that through the DI system. Its not a major issue as I'm use to tearing down and cleaning my AK.

My biggest concern if I pull the trigger (so to speak) will I regret building a 5.45 AR.  Given ammo prices, I don't want to get back into 5.56 but I do love the AR platform.

Honestly it took me longer to clean my huldra 5.45 upper. The corrosive ammo means you have to use ballistol or boiling water to clean it. Google corrosive ammo and cleaning if you don't know what I'm talking about.

Pouring the hot water over everything then cleaning as I would a DI gun just took more time. Caveat:  I clean everything meticulously including the piston every time I shoot. The parts were cleaner absolutely but when the ammo is corrosive I try to get all that crap out and protect my expensive upper.

I had issues with my upper the first trip to the range but suspect its the magazine.

with a melonite coating on everything you really don't have to bee too anal about it. I have a DI and a Piston that I shoot 7n6 out of and have left them each for probably two weeks after shooting without every looking at them again and no issues what so ever. Yes the corrosive stuff can be a problem, but not nearly as much as its made out to be.

I haven't seen anyone that had qualms with the Adams Arms ne' Huldra 5.45 upper or cleaning.
Appears when they design this, they knew it would be shooting corrosive / low quality (by US standard) ammunition

One of the Huldra guys checks this portion of the board as does someone from Adams.
I would say buy with confidence and report back on your experience.

Edit: Huldra is having a sale on the 5.45. May be a good time to hit the "buy" button.

Where is this "Huldra sale"? The website shows the 5.45 upper out of stock and doesn't seems any cheaper than it normally is. (Huldra site links to Fleetfarm).

Edit: ok the 5.56 is on sale but not the 5.45 upper.

Ughhh...
I looked too quickly. Yes, it was the 556 entry level model on sale.

I've been using my AA 5.45 for about 2 years now without an issue or major issue.  It did take a little shooting to break it in properly to get it functioning on Wolf ammo but, never an issue with 7N6.  Cleaning is way easier than my DI guns and a lot faster.  I've been using Frog Lube and found cleaning was even faster as a majorty of the bolt cleaning just wiped off.  Hot water is not necessary to clean and good old tap water will do fine.  You can spray it down with windex too and clean as normal.  I did a lot of reading on cleaning the AR with corrosive ammo prior to buying mine.  I noticded a lot of people who use water and have found rust don't do anything to properly dry or remove the water.  Then they blame the ammo for the rust.  My trick if I cannot use the air gun from my compressor is to let it air or shake dry then spray it with WD40.  This pushes out the water from under the gas block and other tight spaces you can't reach. Then clean as a normal gun and that's it.  About 3 months ago I changed to a free float rail and the barrel nut and gas block was rust free.

Ain't that a bitch, I bought the 5.56 3 weeks ago at the 599 price. 25 bucks is a couple boxes of ammo.

:)
http://www.ar15.com/forums/t_3_12/626098_Quality_components_while_NOT_paying_for_a_name_.html

Corrosive ammo does NOT require Ballistol and boiling water to clean.  It requires hot, soapy water, some elbow grease, and attention to detail.  Hot water evaporates quickly, which is why you use it, and how do you get hot water in the field?  Boil it.  At home, you don't need anything but very hot tap water  The soap helps break down the crud while the water dissolves the salts left by corrosive primers.  After making sure you've gotten all of the barrel and gas system, you use standard cleaning materials to finish cleaning the gun.

Since Huldra uses all Melonited parts, you will probably not need to work very hard at cleaning the upper.  Melonited surfaces are very smooth and stuff just doesn't stick to them the way it can to other, non-treated surfaces.  I would still use hot, soapy water, but the scrubbing part is probably going to be minimal at worst.

A lot of people forget that they also should pay attention to their lower when firing corrosive ammo in an AR.  For that, I'd use something like Slip 2000's 725 cleaner/degreaser, because it's water based.  Just spray a bunch of it into the FCG section and swish it around with a toothbrush, then spray again to "rinse."  It really does degrease VERY well, so you need to re-lube everything afterward, but that's part of cleaning too.

Who has Huldra uppers in stock?  I haven't seen them available lately...

Fleet Farm sent me an auto e-mail yesterday saying they were in stock; not yet available on the web site, so check tomorrow.

You guys spend a lot more time cleaning your uppers than I do.  I take about 5 min in the field after shooting, quick cheap and easy.  Main goal is to just wash out the salts.  Every few spam cans or so I do a ultra sonic cleaning but otherwise no issues with my field cleaning procedure on my 545 upper or my ak74.  Several, several thousand rounds through my upper in the name of "product testing" .

Dave