More expensive tips are generally made of virgin abs plastic.
A cheaper tip is made of the re-melted off-cuts. This tends to add slight impurities, it also looses its flexibility in the process.
Cheaper tips tend to be thicker, so add unnecessary bulk to the enhancement.
More expensive tips tend to have greater uniformity, so you know each time you order they will be the same colour, shape etc.
Sometimes cheap tips don't always end up being as economical as you think. They often don't last as well, discolour and become brittle with age.
I use ProImpressions tips too as I find they are both great quality and great value.
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