Ok, I couldn't wait any longer so I cut off the plastic strip between bench-top and wall and replaced it with silicone. 20min job but a lot better result of stopping the water from going behind the bench-top, down the wall onto the floor.
First I cut off the strip with a Stanly knife and cleaned the area very well so silicone sticks 100%


Tape up all your joints with masking tape. Top and bottom of the joint, be careful here spend a lot of time doing this as a straighter lines will give you a much better results. Also make sure your corners are spot-on as well.



Using your silicone of choice (I used Sellys "Wet Area" sealant IVORY) pump silicone into the joints. Try to get as much as possible into the actual joint leaving a bit over the top for smoothing out later.
Sorry I missed a photo here.
Next smooth out the silicone with your wet finger. Make sure you wet it as this will give you a much smoother finish and won't stick to your finger as much. Try and run each straight with one motion to give it a nicer finish.
Wipe off any excess on a rag. Keep wetting your finger and smooth out all the joints and corners, you can go over the same joint again to make sure it looks good.
Remember to push silicone into the joint at this stage as well. don't take too much time as you don't want the silicone getting to dry.


After you finished smoothing out the silicone, you need to pull all the tape off. Try and start at the end where you started the smoothing part and pull the tape off slowly and on a kind of 45deg angle away from the joint. Take your time so you don't get it all over your bench or wall. If you do then vinegar is your friend here. Get a cloth soaked in vinegar and wipe off.
If you leave this part for too long than you might end up with a little edge on the silicone where it meets the tape. You can then wet your finger and smooth it again.
Then you have the final product....



First I cut off the strip with a Stanly knife and cleaned the area very well so silicone sticks 100%


Tape up all your joints with masking tape. Top and bottom of the joint, be careful here spend a lot of time doing this as a straighter lines will give you a much better results. Also make sure your corners are spot-on as well.



Using your silicone of choice (I used Sellys "Wet Area" sealant IVORY) pump silicone into the joints. Try to get as much as possible into the actual joint leaving a bit over the top for smoothing out later.
Sorry I missed a photo here.
Next smooth out the silicone with your wet finger. Make sure you wet it as this will give you a much smoother finish and won't stick to your finger as much. Try and run each straight with one motion to give it a nicer finish.
Wipe off any excess on a rag. Keep wetting your finger and smooth out all the joints and corners, you can go over the same joint again to make sure it looks good.
Remember to push silicone into the joint at this stage as well. don't take too much time as you don't want the silicone getting to dry.


After you finished smoothing out the silicone, you need to pull all the tape off. Try and start at the end where you started the smoothing part and pull the tape off slowly and on a kind of 45deg angle away from the joint. Take your time so you don't get it all over your bench or wall. If you do then vinegar is your friend here. Get a cloth soaked in vinegar and wipe off.
If you leave this part for too long than you might end up with a little edge on the silicone where it meets the tape. You can then wet your finger and smooth it again.
Then you have the final product....


