I play EU for 3 years and AW for 4 months, playing both for several hours every day, and love them both equally. There are many similarities and much more differences, but I don't compare them, they supplement each other for me.
EU for me is a casino in the finest sense of the word, not a one-handed bandit, but a poker: if you have a knowledge you can be successful, but not all the time and you should never relax. And you should be ready to lose a lot and do not whine. I know all that and it's ok, so when I want to try my luck, never knowing would I profit or completely broke, then it's time to go to EU. I'm not a high level player in the terms of gaming style (keep hunting mostly argos, feffs and rarely atroxes for the last 2 years using primarily Isis lr32) so I don't spend thousands dollars, to keep my head above water 100-150$ per month is enough. As a downside of a such style I don't get much skills, because had maxed all the weapons I usually use over 2 years ago - in the whole 2008 I did progress only from 42 lvl Laser Sniper to 47 and Agility from 62 to 67 (and I play EU 3-4h/day, every day)

. But since I accepted the fact that I'll hardly ever reach 70+ lvl, the skills don't matter much for me, I just enjoy the gameplay, hunting my favorite mobs, spending time with my disciples, visiting various events etc.
AW is a completely different thing. I almost didn't gathered sweat in EU, only tried it a bit and found deadly boring, not saying it's close to impossible to earn anything serious with it. But I really liked picking stones in AW

. People talk A LOT in the Quarantine zone and you see whole zone local chat, not in the radar vicinity, so even if you won't ask questions and will just read the chat while picking, you'll soon learn more about the game than 10 good mentors could teach you

. You can donate 10$ right away, buy the citizenship for 100 AWD and leave the zone, but will have neither knowlegde about the game nor basic skills which you get while picking, so the people who left the zone too fast usually come back pretty soon.
I chose to pick my way out of the Quarantine and in 1 week of playing earned enough to buy me a citizenship. Also earned many friends and a lot of useful knowledge. Only after that I donated 20$, it brought me 200 AWD (AfterWorld Dollars, the rate to $ is the same 1:10 as for PED) to be able to craft pickaxes myself in big amounts (you can't craft in the Quarantine zone and have to go to the other town to do it, and it's really not an easy and fast trip). I kept picking for several weeks, earned ~700 awd and gathered dozens tones of ores, and then finally left the Quarantine zone to start skilling hunting. Skills I gained while picking allow me to craft weapons and healing kits myself and that's 2+ times cheaper than to buy them. I skill like crazy and progress pretty fast. I fell in love with the crafting system, it's complex and amazing. I never had a chance to be a crafter in EU, it requires crazy amount of money to skill. In AW crafting is always 100% successful and the material prices are laughable compared to EU. So far I donated only 100$, the last time was 3 months ago. Probably I'll donate more money in the future, but only to support the developers, because I have enough of AWD without donating, I don't lose them, because there is no Luck involved. As I said above, to try my luck I have EU

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