Well, couple obvious differences, they were metal back then, Forged Iron -tier. Metal has (I think) a bit of resistance to zed attacks, so the 2500 hp seemed more than it was. Now, unless you've gone all the way to steel, you won't have that protection. Then again, as my shoddy memory serves, I think a concrete Bars block already feels stronger than the old Iron Bars.. I tend to stunlock the zeds with fences, so they don't really do much either way .. wood would be fine, just took half a horde with just one ele fence; until the third demo took the post out. Wasn't expecting any demos yet, so caught me a little by surprise ... 
Edit History
Please note that revisions older than 365 days are pruned and will no longer show here
Well, couple obvious differences, they were metal back then, Forged Iron -tier. Metal has (I think) a bit of resistance to zed attacks, do the 2500 hp seemed more than it was. Now, unless you've gone all the way to steel, you won't have that protection. Then again, as my shoddy memory serves, I think a concrete Bars block already feels stronger than the old Iron Bars.. I tend to stunlock the zeds with fences, so they don't really do much either way .. wood would be fine, just took half a horde with just one ele fence; until the third demo took the post out. Wasn't expecting any demos yet, so caught me a little by surprise ...