covering cracks with paint. Texture coat ?

hello all,

I have just pulled out a sliding door and part of a wall in between the kitchen and dining room to open it up a bit. On one side i have bricked up part of the cavity that was the sliding door and then had it rendered. My problem is with the join where the new render meets up with the existing render. Had a few renderers quote the job and all of them said that it would be a good chance that the join would be slightly visible, and although the renderer who ended up doing the job did a good job i dont think that standard paint will cover the join. Does anyone know of any good texture paints that i could paint the entire wall with that would cover the join. I had a quick look on dulux website they have an exterior Medium texture paint that is meant to be 4-5 times thicker than standard paint. Do you think this would do the job. Anyone used this or similar products.

Any thoughts appreciated

Peter