It depends on your definition of what "decent" means. Once you determine what that is and the purpose, then a determination of what ammo to recommend can be made.
Plinking and training, whatever FMJ load you can get cheapest is likely to work well enough. Recently, Wlamart clearanced out their 420 round XM855 cans for $60-$70 and I bought what I could find. More often I am pricing out various sized packages at the stores I frequent or the online stores I use for the lowest prices. Sometimes the 20 round boxes end up cheaper than bulk packs.
For HP or SP rounds, see the above. Fiocchi, Federal, and Remington have bulk packs ranging from 50-200 rounds of 50 and 55 gr bullets often for reasonable prices. The store I work for clearanced out 55 gr Win SP for $5/20 a couple months ago which wasn't bad.
If price rather than bullet is your main consideration then the "best" choice will vary from manufacturer to manufacturer and from store/supplier to store/supplier.
Both will probably suck for groups. Both will train and plink fine. Both will penetrate more than enough. If one is closer in weight to your other target/hunting/defense loads, I’d probably rock that one. 1:8 wont know much, if any difference.
I'd kinda like something that doesn't suck, for groups.
If you need specifics let's start at .5 MOA and work outward towards 2 MOA.
which bulk loads won't break the bank?
John, depending on your rifle, .5 MOA is a tall order. You can check the 24hourcampfire Black Rifle Challenge thread to see what some very experienced guys are getting with their individual rifles. I think you'll find .5 MOA to be a fairly challenging result. To get .5 MOA consistently out of any factory ammo is a tall order.
You got some good advice in the other thread, too. I would check ammoseek.com after you come up with a couple rounds that are well-liked across the board. I believe you were on a good starting track with the XM193. They may not be .5 MOA, but they're pretty consistent. There are others. I keep a fairly good stock of XM855's for training, plinking, and SHTF stash. I do not by any means consider them an accuracy round. Hopefully, some other members will chime in with some different rounds they like.
You might also consider trying some heavies. I just bought a couple thousand rounds of Black Hills and IMI 77 gr Sierra Match King BTHP's to beef up my stock of those and run in my SD get the fugg out of here / away from me BCM 11.5" AR pistol. The Black Hills is top tier factory ammo, and doesn't come cheap. The IMI is an Israeli product, and good ammo. With your 1:8 barrel, they may put you closer to the .5 MOA you seek.
Keep an eye on the holiday sales. This is generally the best time to buy. Labor Day is coming up, so that should present some opportunities.
Good luck and Keep the Faith.
