The fun part about the website, is that it allows you to customize your character. You can select from a variety of different parts of the character including head, hair, eyes, teeth, body type, clothes, weapons, accessories, and more. This allows for a high level of uniqueness.
There are limitations though. For example, the last time I played with the site, I could not create a character with a sword pointing down to the ground. In this picture, taken from the blog Minismith's Minis for Ebay, http://minismithebay.blogspot.com/2010/11/ral-partha-wizard-female-ogryn-and-2.html, an old Ral Partha miniature, something like Wizard with Runesword, the figure is pretty much exactly what I would like to make but in a more modern scale. Not possible.
As far as I can tell, you cannot have a character that wields a weapon with two hands either. This leads to some odd poses with characters that are yielding say, greatswords.
The current races are also 'mainstream' in that you have the following: human, elf, half elf, dwarf, gnome, halfling, half orc. The good news is that they also have the following: elemental (gensai), half-demon (tielfling/cambion), and robot (warforged). Sadly, no half dragons or half giants. You can cheat on the later thought as you can control the size of the character to a certain extent.
One aspect that is far ahead of most others, is that while fantasy may be the most popular, it does include settings for the following genres: fantasy, western, sci-fi, modern, east Asian. This allows you to cover a wide swath of characters that outside of boutique companies, are rarely covered.
My friend ordered several of these. Some of them directly for character's he's playing in a Dungeons and Dragons 5th edition campaign and others because he thought the ability to mod your figure awesome.
The miniatures were well packed and arrived sound and secure in a box with bubble wrap. Each figure was individual wrapped and no figures suffered damage in the transit.
In terms of the size compared to other companies?
In the first, we have a dwarf from Stonehaven miniatures next to an elf from Hero Forge.
In the second, we have a crouching human next to a miniature from Wyrd, an old metal Guild Captain.
Here are my observations from painting several of them:
1. Size is fairly close to standard in the industry. As much as there is a standard.
2. Detail is soft. I'd say somewhere around a fair Mage Knight or other prepainted miniature. The more control you have over your brush, the more you'll be able to bring out those details. Some of that detail is so soft though, that you will not be doing things like drybrushing unless you have fantastic control. The same is true for washes. Without deep recesses, the wash has nowhere to go. Note this varies depending on the model. In the below, the tabards don't necessarily have a lot of detail. The cloaks have enough to make it easier with washes, layering or drybrushing.
3. Printing Artifacts: If you were to hold one of the figures and look at it under a strong light, you would see the remanents of how the pieces are created. This looks like waved texture. It's so slight though that it does not show up when brushed. Some may want to file it but that seems a bit extreme.
4. Fragile to a point. I have several miniatures from Gale Force 9 for their Dungeons and Dragons line. Perhaps due to how the dynamic poses are set, I've broken a few of them. I dropped a knight from my friend's order and snapped the blade right off. The good news is that it was a clean break and easy to repair with super glue. Now mind you, that would probably happen with metal as well. Handle with the same care you do resin figures and you should be okay.
5. Paint Adhesion: I tended to use two spray coats of Army Painter. I started with black and then over the knights, plate mail. On the wizard and warrior, I did a zenith primer of white over the black. Despite that, there were several spots on the miniature that did not take paint easily. Note this was after I washed them in warm soapy water and used a toothbrush to scrub them.
The initial offering is strong. The biggest hurdle for casual users like myself, is price. At $25 a figure, these miniatures are directly competing with top tier brands on a per figure. On something inexpensive like Bones or a set of plastic? If you have a specific figure you want created, such as my friend did with a duelist with two rapiers and a crown, the price is worth it.
Is you just want something to paint? There are a lot of options at that price point.
As Hero Forge expands it's utility, not even necessarily in terms of detail, but in terms of variety, the value will increase. For example, if there comes a point where you can select from twenty different historical styled helmets or different types of clothing representing specific eras, people will pay more for that.
As more options in the positioning of the figures is increased, people may find something that gives them a better match. The ability to have a miniature using a two-handed axe in two hands for example.
The more specific your character need, the more specific the miniature you want, the stronger the appeal of Hero Forge.
Keep an eye out on them. It won't be long before I suspect Hero Forge will make it's money selling you the CAD's for printing at home.