I must say, it is a lot of fun. I didn't care much for the story with the Mechanist and the ending is meh.
One of the selling points of Automatron was the ability to build and customize your own robot companions, and I must say, this is some serious Robot Wars shite there! I constructed a Mr. Handy with a saw on each thruster arm, a Sentry Bot arm with a hugeass sawblade and a laser hand.
Along the way you will pick up some mods for your robots, I built a Raider Mr. Handy which looks kind of interestingly badass with spiky, thorny armor. You'll pick up Protectron, Assaultron, Mr. Handy, Sentry Bot mods, and the Robobrains from F3 also make a return.
As long as you have the resources you can build as many robots as you want, and while they do not count towards the defense rating of a settlement (much like companions) if they are well-build they can be pretty damn efficient as my four sawblades and laser gun Mr Handy can attest. You can choose a paintjob and voice as well, and several upgrade give those robots a very damn good carrying capacity, so not only do robots pull their weight in combat they can also double as pack mules.
I usually don't care much for companions but robots are morally neutral and will not give a toss about anything you do, which is awesome, and Zaratronok more than pulls his weight in combat. Hell, this guy can take out Super Mutants on his own and he took down a two Masters in the bloody Medford Memorial Hospital!
Is Automatron worth the price? The plot is meh (no surprise there) but the fun of making and tinkering your own robots (including Codsworth and pre-personal quest Curie), I'd say it does, just for the Robot Wars Frankenstein robots you can make, especially when all the upgrades have been unlocked through picking up parts from various robots.
As soon as I get Science 3 Codsworth is becoming a Sentry Bot, finally!
SKELETONS RIDING OSTRICHES