Lip treatments at £30+ rarely outperform Vaseline (petroleum jelly) or Aquaphor. The job is to prevent water loss from lips; petroleum-based occlusives do this best. Premium ingredients in lip products are mostly marketing.
What lip skin actually needs
Occlusive layer to prevent transepidermal water loss. Avoidance of irritants (menthol, camphor, fragrance often dry lips more than they soothe). Daily SPF on lips (Aquaphor + SPF lip balms layered).
When to spend more than Vaseline price
Lip serums or balms with active ingredients (retinol for lip lines, peptides for fuller appearance) at evening only. Lip masks (Laneige Lip Sleeping Mask) for an overnight intensive when needed. Mostly though, basic petroleum jelly is the workhorse.
Skip £30 lip treatments. Vaseline plus an SPF lip balm during the day covers 95% of lip care.