I have both DKL2 and DKL3 and would never touch them again now that I have the SNES games available in portable form thanks to emulation.
DKL1 miiiight be worth trying due to its unique music and level design, but the latter two are pretty much straight up ports with some changes that were required due to the much lower capabilities of the Game Boy.
Overall, much like with a lot of portable ports, I find the main draw was the fact that they were indeed portable versions of the original. Now that emulation and emulation devices have advanced to the point that the original versions are portable as well, their primary draw has been pretty much wiped out, leaving only a sub-par version of the original game most of the time. Sometimes, there were ports that actually stood out due to some unique twists, but at that point, you start arguing whether they're still "ports" or actually some form of spinoff. DKL1 falls somewhere inbetween the two sides, clearly grabbing the gameplay straight from DKC1 but doing its own thing with the levels.
So to answer your question, OP, I believe the DKL titles have not aged well at all. The thing that made it great back in the day no longer really applies in this day and age, so unless you're really into the history of the Game Boy for some particular reason or you consider the original music and levels of DKL1 to be worth putting up with the inferior screen real estate, graphics and control, I'd say stick to the DKC games.
But really, you're asking a bad question because everybody has their own definition of what a game "aging well/poorly" means (including the definition of "it means nothing at all because games don't age").
