I decided to give it another try and enrolled to sites which are so called "Big 7":
Since I am newbie I decide that I will try to upload 500 random pictures from my collection to see how it would work for me. I did not make any particular selection, I chose randomly. Different sizes, subjects, quality.
Shutterstock. The number one site for microstock. It is truly efficient. Uploading thru FTP took 8 hours. The you can submit pictures in 50 piece batches. User interface is ok but I wish it remembers tags I used before and somehow let me to reuse them. They are quite strict, my rejection rate is about 90% but in couple cases I thought photo is bad and not interesting but they approved it. I am in the middle of submitting process so I can give exact number when I am done. They are quick, most photos were reviewed on same day.
Istockphoto. I am a little disappointed with them. After whole day it's still not up and ready. I had to upload my photo id twice and approval is still pending.
Dreamstime. I can upload only 100 files. FTP upload is available but I blocked my bandwith trying to finish upload to other sites :-)
Fotolia. This are the guys. I tried while ago. It took almost whole day to upload 500 files. Submitting interface is a little better. It remembers categories but still do not remembers tags. There 10 photos displayed per page so it would slow me a little even if it seems to be easier to fill data per each photo. After one day they did not touch any of my pending photos.
Stockxpert. They wanted 10 photos for approval first and do not give any status for this process.
BigStockPhoto. FTP works but I am limited to 250 pictures. In addition to that they only review 20 photos at the time so I am done here for a while. I hate that they not only require 7 tags like others but also at least seven words description. Category selection also sucks.
123rf. FTP upload seems to be quite fast but then if I want to display pending queue it is not paged and tries to download huge web page :-) They also want photo ID for verification.