I'm quite happy with iWriter. The payouts are not high, but it is possible to invest your time and earn more. In the beginning 400-word articles bring you $2.03 and 500 $2.43 but once you spend some time writing good articles and reach 30 written articles with average rating of at least 4.1/5 you will be paid double and if you reach 4.6/5 it will double again. Meaning that it will be possible to get over $20 for a 1000-word article if you have invested into building a great profile.
If it's interesting I'd be happy if I could refer you to sign up [can't put the link here, unfortunately]
Once you'll have written a few articles you can also activate your own affiliate link to recommend to your friends and therefore get a small bonus on each article they write. Naturally, it's not the writer's part, but the website's part which gets distributed, so no worries.
There are no minimum payouts and money will be available on your account the moment the article gets accepted, the requesters have time limit of 72h to assess your work, so that's the longest it can take.
I signed up only a few days ago and I like the site a lot. I've written 5 short 400-500 word articles, whereas one was rejected. This still means $10 revenue on few hours of work, which compared to websites where you have to rely on traffic to earn, is really quite a lot.
At any given time there seems to be available about 10-25 Elite tier articles which are the best paid, over 150 Premium tier articles which still pay pretty good - over $4 for 500 word articles which talented writers can easily finish in 30 minutes and a ton of Standard tier articles to quickly get your reviews.
The only downside is that in the beginning you can churn out articles only every 40 minutes! So if you'd like to spend some time I suggest you write an article, hit Send and then during the 40 minutes, you pick out one or two interesting titles, have a look at the special requirements and do the needed research. When the 40 minutes are up you can then write the article in no time. Try not to use Word and write the article wholly on their website - doing otherwise might introduce broken characters to the article and it might be rejected more easily and you'll be sure to get a lower review.
One idea - every writer will get their articles rejected every once in a while - for me that's not a catastrophe. As I only choose subjects which are remotely interesting for me I will turn the rejected articles into Hubs.