There are a lot of really good company’s out there and a few trash.
My favorite for Autoflower Strains are Fast Buds 420. They have great Autoflower genetics.
Then I would say you cannot go wrong with the old school time tested company’s like Green House Seeds, Barney’s Farm, Dutch Passion, Royal Queen Seeds. They all do very well in research and development and field test their strains before they release them to the public. There are some new and upcoming seed company’s that are really making a splash like Umami Seeds who has just been picking up steam because they care more about Flavor then anything else so they have been known now to produce some great tasting strains.
My favorite seed bank is Attitude Seeds. Used to get them from the UK site but lately they have been having a hard time getting them into the US. If you are in the US I suggest ordering straight from the US Attitude Seed Bank site. If you are not in a rush, they do alot of promotions giving away free seeds. My last order was 10 seeds and I got 12 seeds free.
I hope this helps.