I don't see Aftermath guns being good entry-level guns in their stock form. They're too hit or miss. There are those that have put tens out thousands of rounds through stock Krakens and haven't had any issue. Others have them break out of the package. That's horrible for someone's first gun when they have no idea how to repair it and don't have access to a gun doc.
But Krakens aren't totally useless guns either. As an upgrade platform for project guns, they're ideal guns. They're an affordable platform to start with, and for a few hundred bucks, you can have an all-metal and wood AK with quality internals for cheaper than a new Tokyo Marui and that will perform every bit as well and be more powerful.
With a proper reshimming and greasing out of the box (just like most would recommend with even a higher end gun), they can be a dependable backup / loaner gun too. As long as you know how to do your own repairs, the parts that are likely to fail in a Kraken are fairly cheap (air nozzle, tappet plate, piston), making it cheap to maintain.
A good entry level gun would be one that like Amos said, that can perform consistently and dependably for a long period of time. Now that being said, it's really more about the number of rounds you put through it than time. Some people put a lot of rounds through their guns while others only fire them at games. And while some Krakens do fall in that category, most don't