BlueMist is awesome. Over 250 juices and super cheap prices. All their juices are made fresh and you can get them in either 80PG/20VG or 100%VG, I recommend 80/20. They offer extra flavor shots for .50cents more and if you find a juice you really like you can get a 180ml bottle for only $30 which is dirt cheap and a deal that cant be beat. Im borderline addicted to their Cafe Caramel juice. Im on my third 180ml bottle and three of my friends who I recently turned on to vaping all vape Cafe Caramel regularly now too.
Ive never ordered juice from ecigexpress so I cant say anything about them.
BlueMist doesnt sell hardware, but they do sell alot of DIY supplies. I bought all my DIY supplies from BlueMist and they make great juice. They have numerous mg/ml options for nic base and different size bottles, their PG and VG is extremely cheap(only $4 for 120ml), and they have an array of options for empty bottles, syringes, pipettes, etc. They also sell a bunch of stuff that isnt necessary to make juice but can help make juices better, like menthol drops and crystals, sweetener, ethyl maltol, and a liquid that gives a cooling sensation on exhale.
They also sell the DIY flavoring for every juice they sell (over 250), which is awesome and I dont know any other vendor that does that. Alot of vendors refuse to say how they make a certain juice so you have to buy it from them, but BlueMist encourages you to make their juices yourself by selling the DIY flavoring for every juice they offer, and then you can make them yourself for even cheaper than their already cheap pre-made juice prices.