The Llanelli outfit - who return to GUINNESS PRO12 action on Friday night at home to Glasgow Warriors - suffered reverses at the hands of Northampton Saints and welsh rivals Cardiff Blues in the LV= Cup.
But full-back Steffan Evans, prop Wyn Jones, fly-half Josh Lewis and flanker Sion Bennett were among those to shine against the Blues, and Wales international McCusker believes progress has been made.
"It has been quite refreshing," the 28-year-old told the South Wales Evening Post. "The youngsters have come in and they are keen to do well and it reinvigorates you.
"It has also has been good for me after a couple of niggles that set me back a couple of weeks. I haven't been able to put any game-time together so the last couple weeks have been good.
"There are a few boys there who are wise beyond their years in rugby terms and it bodes well for the Scarlets.
"These boys have been performing week-in, week-out in the Premiership and deserve their chance.
"I didn't have anything like this when I was their age so it is great that they will be that more experienced when they do break into regional rugby.
"This tournament bridges the gap between Premiership and regional rugby and gives them a lot more exposure to that higher level early in their careers."
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