Actually, MODs, I'd like to request a sticky in the rules section. No offense to themuffinman873, but so many people miss what actually has to happen to invoke Army Book > Rulebook (that there has to be actual conflict between rules), and it's such a Frequently Asked Question (so much so, that you might think GW would FAQ it), it would just be great to be able to point people toward an explanation of why the AB>BRB does not apply here and thus why Supporting Attacks and PF don't play together. With almost zero exception, once you take a person through the "why" they get it and (begrudgingly in some cases) accept that the rule is marvelously clear for once, but it's such a pain to have to walk the path over and over again.
As to the OP's question, yeah, the debate is out there still, with HW+SH being the more generally useful build but Spears not being a total waste either.
If you think you can get an Ancient Stegadon Engine Thingie to live, then the Spear version gets a nice tick upward. If you have a way to consistently make the extra 5-10 Attacks have a real impact, then Spears get the nod.
If, on the other hand, you want a unit that is a little more self-reliant on Defense and/or you don't trust those extra few Attacks to do much, then HW+SH is the way to go.
Point of note to tie it all together - If GW ever did make an errata to change the rules for Supporting Attacks (or if 9th changes them), then Spears will merit significantly more consideration.