Are there any good V4 eye sets (MAT poses, not merchant resources) that anyone can recommend?

I highly recommend "Eye Maps: Generation 4" at DAZ. It's the most complete and well organized set I've seen. Once I bought this set I stopped looking for other eye sets for V4. www.daz3d.com/i.x/shop/itemdetails/-/

Coldrake

Predatron's Total Eyez system are great but that will actually replace the whoel eye geometry on V4 for a new eyeball:
http://market.renderosity.com/mod/bcs/index.php?ViewProduct=53260&vendor=167783
I haven't used the V4 onebut I do have the G2 version and I can't say enough good things about the Total Eyez.
The big drawback is there aren't much in the way of additional textures for them so you are more or less stuck with the colours that Predatron has included.

If you want to stick with the standard V4 eye geometry then my advice is use Rebelmommy's eye packs.  These are my preferred solution for V4 and no only can you get different eyes in every character pack but she does have some stand alone eye packs on themarket as well and they aren't merchant resources:
http://market.renderosity.com/mod/bcs/index.php?ViewProduct=61531&vendor=276283 (I haven't tried this pack and to my eye it is possibly the least aesthetically pleasing of her packs)
She also has a set of True 2 Life Eyes for V4 but I have checked her stores here and at RuntimeDNA and cannot see them on sale at either store.  Maybe drop her a site mail and ask about them, she is very, very approachable and gives great customer service.

Did you mean this one of RM's? I don't know if she changed the name or something but anyway this is the pack I have and it's really good - mat poses as well as the merchant thingy.

http://market.renderosity.com/mod/bcs/index.php?ViewProduct=61531&vendor=rebelmommy

That's a newer set.  

I have a set by her called True 2 Life Eyes (in fact I have 3 - one fr the Mil3 females, one for the G2 females and a V4 one) which I think are actually nicer than that pack - no idea where the V4 ones have gone though because the G2 ones are at Runtime DNA and the Mil3 ones are in the store here.

After buying multiple eye sets I can definitely say that the Daz ones are really the best.  They were more than what I initially wanted to spend so I tried others instead and ended up wasting too much money that way.  The Daz set really is worth the investment.