Some products streak more, some less, some dont... If it streaks, you need to work a bit more to make it go away. Change sides of towel frequently.
Yes, water beading is one of the metrics for checking the existing of wax. When you wash it with a shampoo, just make sure the you use it in diluted form (and not directly applied to the cloth like service walas do).
Detailers do have cleaning ability that mostly dust oriented. Using the same product detailer as wax will complement the wax in rejuvinating the loss slickness over time.
If you are up to switch to Meguiars, you could get yourself a
Shampoo : Meguairs wash n wax (so when you wash your car, it will put a slight layer of wax) ~ 1500 Rs 1.5 ltr
Wax : Meguiars ultimate paste wax (this is a synthetic wax) ~ 3000-3500 11oz jar
Detailer : Meguiars detailer ~ 1500
Optional : Meguiars ultimate quick wax (this can be a booster wax that you can use after every wash and it will offer a sacrificial layer on top of main wax coat)
There are lot of products that you can plug in between the above steps, but this is good enough to get started. Ofcourse has a cost involved. You could first get yourself used to wash n wax with the turtle range you already have and if its not being too much of a pain then wait for them to finish and get yourself meguiars range. If budget isn't a issue and car care is priority, get yourself meguairs range.
People from karachi can tell you where you could find these but you could google it up with pakwheels.com reference in search query and it should bring you a few shops name.
