4 On Us

I’m considering switching from T-Mobile due to rising costs. Verizon’s “4 on Us” promotion offers four iPhone 16 Pro devices for free when switching and trading in eligible phones. This requires activating four new lines on the Unlimited Welcome plan at $25 per line per month, totaling $100/month, plus taxes and fees. Can someone advise me on how good this deal really is ? Any hidden cons?