Kenwood and Pioneer, both manufactures cool and affordable double din head units according to my personal experience.
Totally agree, Kenwood and Pioneer are the best brands for head units by far. I've had both in my car and they're both amazing. I would highly recommend either of them to anyone looking for a new head unit. However, you need to be careful when buying a head unit. Make sure you get one that is compatible with your car. Some cars have different systems that require specific head units. Do your research before you buy! Aftermarket head units have different types of equalizers and amplifiers. You need to make sure you get the right type for your car. Otherwise, you might not be able to use all the features of the head unit. Some head units also come with GPS navigation. If you're looking for a head unit with GPS, make sure you get one that has good reviews. There are a lot of bad GPS units out there.