We're going to get a little obscure with Hightower's comp, former Cardinals and Chiefs receiver Steve Breaston. Like Hightower, Breaston was a fifth-round pick in 2007. In addition playing receiver, Breaston returned kicks and punts, something that Hightower did in college at Boise and should get an opportunity to do with the Eagles.
Both players were lean receivers with decent speed and playmaking ability. A comparison of their measurables:
40 yard dash
Breaston had a short career, but he did rack up 3,221 over a four-year span from 2008-2011. A look at Breaston: