+1 on Krebs and Arsenal
All the Arsenal AK-74s are actually Saigas. I believe it is the same for Krebs but I'm not positive. I have an Arsenal and so know more about it. I'll tell you what I know about it but the little I know about Kreb's guns is that they are top quality as well.
Arsenal buys and imports these
or partially built guns directly from Saiga. They have to come this way because of import laws. Then, Arsenal under the direction of Saiga gunsmiths or with Saiga trained gunsmiths converts them to these
and adds all the compliance parts to make this configuration legal. My guess is that Kreb's does the same thing or does it for customer supplied rifles. Either way, these two are the tops in quality for the AK-74 unless you find someone out there who hand builds them.
I bought the Arsenal because it was available and cheaper. Keep in mind that most AK-74 type rifles are going to be more expensive than the 47s simply because they are rarer due to less demand. You are also going to pay more for the Russian Arsenals and Krebs rifles than you will for other brands or other countries of origin. I also prefer the stock, no frills, original AK set-up of the Arsenals. I'm guessing that Krebs does it too but they seem to do more custom builds than original configurations. I'm betting that the small-batch, custom nature of Krebs builds that they may have the edge in quality of build. I do not think this edge equals a night and day difference between them and the Arsenals but it also translates into lower volume and higher price over the Arsenals.
I'd say buy either one. Both are the top of the list in quality and with the cheapness and availability of quality, surplus, bulk 5.45 ammo you are still getting a bargain over the life of the rifle even with the increased cost up front.