I know nothing about 2D20, so feel free to educate me on that as well.
I am also one of those people who actually enjoys good RPG art, so let me know if the books have any good inspiration in that regard (I can see the covers, but inside art?)
I was initially a critic, but CRKrueger's posts here actually convinced me to take another look at it. I have ended up liking it quite a bit, though I have yet to run it.
I expect there to be pretty overwhelming negative responses on the mechanics, given previous threads here, especially around the metagame Momentum and Doom pools. I personally had an issue with them too until I got my head around how to use them and how I could modify the use to my taste. Instead, of wading into that, I will recommend you check out the free Quickstart (http://www.drivethrurpg.com/product/174829/Robert-E-Howards-CONAN-Roleplaying-Game-Quickstart) and make your own call on the basics. Its a pretty detailed in its coverage.
As to the art, I think its good also. Both the corebook and the adventure book released to date have decent amount of art which is either average or good quality. The layout is clean and readable.
There was a thread about the system not too long ago that you can check out here: http://www.therpgsite.com/showthread.php?35911-Modiphius-Conan-System (http://www.therpgsite.com/showthread.php?35911-Modiphius-Conan-System). I'd second Skywalker's suggestion and check out the quickstart, though.
My own thoughts are based on reading the quickstart rules and Internet discussion, not playtesting, so take them with a large grain of salt. I don't care at all for 2d20 as the die mechanic feels gimmicky to me, and characters seem like they'll almost never succeed at tasks of any difficulty without Doom (which I really dislike) or being unbelievably lucky. Coriolis uses a similar mechanic in Doom Points and they'll be the first thing to go under the knife if I ever get a chance to run it. Some of the uses are fine, but a lot of them either hamstring the GM or needlessly screw over individual players.
Thanks for the info folks!
Yeah, off the top of my head, there were (at least) three major threads on this forum discussing the system, with the designers participating in at least two of them. The majority of the controversy has been over the metagame Doom mechanics, with some lesser conflicts over the abstract zone system and such. From what I've seen/read (I was a kickstarter backer, but have not read everything yet and have little intention of ever actually playing it), it looks like a good system for a semi-narrative game - I've seen it described several times as feeling like you're a part of a Conan story, as opposed to feeling like you're an actual person in the world of Hyborea. If you're cool with metagame mechanics and narrativey games, you'll probably like 2d20 Conan. If not, you still might like it, depending on now badly you react to them and/or how much work you're willing to do to remove them.
ETA: Just remembered another significant detail. Because a lot of GM powers (bringing in enemy reinforcements, enemies parrying, etc.) are gated by the Doom Pool, debates over the Doom mechanic have also focused on whether or not it's an adversarial mechanic, in addition to the overall metagaminess of it. While most everyone seems to agree that it's metagame, there's no consensus on whether it's adversarial.
I agree with the opinions that the Doom system is at the very least, unnecessary. If I'm DMing a game, I don't need points to tell me if or when I can add additional challenges for the players.
On the other hand, I believe the Momentum system creates a more dynamic combat sequence, and when combined with displays, it creates a cinematic and heroic / kickass feel about it.
My one dislike is that Displays cost a full action and they require a certain sequence of actions to unlock, but their benefit does not equal using and additional attack. I used Displays as a bonus action.
Of all of the RPGs that I have played, CONAN 2D20 is the first that I found who's combat is enjoyable enough to play solo. I don't mean with just one other player, but truly solo. I play tested my adventures before running them with a group and found the combat sequences to be very engaging.
Finally, much like the Conan stories, I found the RPG is ideally suited for Solo Adventures, where the one player character uses a henchmen or two to get passed the more difficult challenges. It is also a lot easier to find one player online willing to show up and run a one-shot adventure.
I can't wait to get the Wave 1 hardcovers in my hands!