I'm surprised no one has dropped in to offer opinions yet. I can't speak for the Hana Modz v4, I don't own one and have never held or tried one. However, on part 2 of your question, I can recommend quite a few other mods that are fairly equivalent in form factor and specs to the v4(s). The most talked about in the forums right now are the IPV D2, eVic-VTC Mini, and the Sigelei 75w. On a personal level, I will also throw in the SMY 60w TC Mini, it performs as well, if not better, than some of those on the list. There are a lot more out there, these are just the top few that are getting all the attention.
I can say from my own experiences that I prefer the IPV D2, SMY 60w TC Mini, and eVic-VTC Mini. They all have pluses and minuses, but they are all performing well for me so far. I have not tried the Sigelei 75w because it just was uncomfortable in my hand, so I chose not to buy it. The D2 is capable of 75w of power, while the eVic and SMY are only capable of 60w (although the Hana v4 is only 40w). They all have the ability to do temperature control, while the D2 and the eVic have profiles for Ni and Ti coils, the SMY does not. The eVic is the only one in the group that has a "bypass" mode, meaning that it will perform
similarly to a mech mod. It isn't exact, but it isn't too far off either.
I carry all of my gear in my pockets, and so far, the finish on all of them seems to be holding up okay. There are no scratches on any of the displays (so far). They all get just about the same battery life in my usage (temp controlled, Ni 200 .15-.24, 420-440 degrees, 24-28 watts). Last but not least, they all seem to be well made and feel good in my hands.
If you follow the link in my signature, you can read my reviews on the D2 and SMY. I have not had a chance to write up my thoughts on the eVic yet, but hopefully it will be posted sometime this weekend.
HTH! I'm interested in what you decide to go with, keep us posted.