Stay indie until and unless you see a clear reason that independence would make sense for your own port. AFAIK, only iS offers artist exclusivity and you need  250 sales. One or two thers may offer image/image series exclusivity. There is no arrangement which is best for everyone, and the goalposts keep changing.

Several sites offer you the option to upload exclusive images. This might be a better solution. You can "reward" sites that do well in a specific genre but can still work with everyone else. You can also join macro agencies like stocksy or getty and still supply others.

Once you have more experience you will learn which of your images can be sold for higher prices and then submit that content ecclusively to specialised agencies.

If you really want to be fully exclusive, then get to know the different agencies that offer artist ecclusivity. istock, fotolia,dreamstime...maybe even get to know their staff personally at an event they organize.

But since there is no dominant site at the moment, and the market is shifting so fast I wouldn't recommend it.

being fully exclusive is very comfortable, but it also makes you extremely vulnerable if the site is not performing well. You are not in control, whatever they do you have to accept it.

The most important is to keep uploading regularly, every month, ideally every week. You need regular uploads and a large portfolio if you want to make any serious money in stock.

thanks all

like i said, i am selling stock trough my agent since 5 years now, i decided to take some of the action to myself and to start buliding the stock more often

there is no rules for selling stock, i had a serires from a place i travel a lot , there are more than 10,000 images in each stock from this place only, for some reason my pictures from there sell sell sell over and over again, but the stock agency didnt let me upload them as they don't have any demand, so i guess this mistery would keep going on and on

thanks for the information
this forum is great, thanks for shareing