I'm sure this has been covered but unless I get a link to the thread its just easier to start a new one. What the opinion on these 2 units in a side-by-side comparison? There virtually the same, except that for 1 more point you get 1 better save and constant 5+ parry. Seems obvious that you would take ironbreakers. However, they occupy special and you need to spend in core anyway, so why not just take longbeards who do it almost, but not quite as good? The bigger issue I find when crafting a list is that I cannot afford a large unit of hammers and a decent sized unit of unit of ironbreakers simultaneously, and a unit at S6 is essential nowadays. You could take longbeards w/ GW, but there the same cost as a hammerer and hammerer's are way better with 2A, stubborn, and 75 point magic std.
I can crunch the math but the difference is marginal, ironbreakers make 1/6 more saves, which doubles in the case of S6 attacks where they would get a 6/5++ compared to just a 6++ for the longbeards assuming they weren't charged that turn.
I'm asking for the longbeards to give me from practical experience which setup is better? I think being in the era of the elf tips it to the ironbreakers, as the extra defense helps to be elves, but I'm uncertain, especially when Archaon and his horde comes to town shortly.