If it's a plinker avoid the HBAR. Unless it was precision rifled by Brand who guarantees accuracy, the extra weight of the heavy barrel just saved the maker lathe time. It might take more rounds to heat up, which may or may not reduce any inherent defects in the barrel steel. It will take longer to cool down, and, it's just heavy. Being "HBAR" is no guarantee of accuracy. The lighter issue barrels are good for 2MOA, which translates to a ten inch circle at 500 meter. That's particularly tight for the average shooter to accomplish and would require a scope. It would be out of range for effective medium game hunting in all but a few circumstances.
The unnamed free float is another consideration. You definitely want to handle it and discover if it's even comfortable for you to use, if it's machined properly, etc. They are typically $200 - add up all the parts cost and even at the bulk discount rates there's not much left in the upper for a quality handguard at the price. Better to spec the lighter barrel and then get a better grade free float.
I did buy a "recon" weight barrel and I do notice it, even in 16". The total weight exceeds an issue M16 with full length barrel, so changes to lighten it up are in the plan. However, the barrel is still going to be heavy and that weight forward can't be taken off easily. With the number of accessories that can be all too easily added, it's better to start light to deal with it, or the legendary 12 pound AR results.
