I have been using a Petzl Tactikka RGB for about 3 yrs now and have no issues, yet, with the plastic failing.
Like you, first impressions, thought the plastic case would not hold up, or at least the tilting head adjustments would wear out or break.
So far so good. I've worn it under house crawl space, into attic, and regular use in garage. The compact size and light weight makes it comfortable when working with hands free.
Yes, the core packs is best way to go. I have a few 3ea and rotate use, never letting them cut-out completely.
If out an about, easy to open up head and plug into car charger.
The core packs are pricey, but check REI or Sportsman's, they have Petzl sales all the time.