Yeah Canna markets to cannabis users and so does Advanced Nutrients, but its just marketing, and they don't grow any better then the other stuff. Advanced Nutrients would be good if they were 1/4 the price. They don't put the best stuff in there (like urea), just okay stuff that gets the job done. Where they do excel is in their customer support. You can call them and they actually will help you out and give you tips. Canna, I haven't used them, but I thought it was weird that so far six people this week have reported problems with them. All new growers so it's most likely the people growing and not the nutrients, but still thought it was weird. Perhaps their directions and support isn't up to par. IDK.
If your going to grow outside and want organic, take a look at Alaska Fish Emulsions and their Bloom fertilizer. Its only $6 and $10 a bottle and I really believe they are just as good as any cannabis specific nutrient. The only downside to the Alaska brand that I can think of is they don't do well in hydroponic setups. To thick and just not designed for that style of growing.
Another brand thats a really good value is X Nutrients. They aren't famous and have only been around for two years, but they are cannabis specific, use good ingredients (no urea!), and they only cost $15 a bottle. If you email the company they might even send you a free sample. Only took me 2 days to get them since they sent it to a local hydro store. I used them during veg last year and I really liked their Grow and Micro. I ran a side by side grow testing them and Advanced Nutrients Sensi Grow A & B. I had no problems whatsoever with them, so this year I decided to try out their Bloom. I might also get the amino blast, just to see how that does. I'm not convinced amino acids are worth buying, but $15 a bottle isn't a big risk. Compare that to $70+ which is what Home & Garden charges or $30 for Big Bud by Advanced Nutrients.
Last nutrient line I'll recommend is General Hydroponics using the "Lucas method" You'll have to google it for all details, but basically you don't need their entire lineup for a nice grow. You can get by with just their Micro and Bloom nutrients.
If you can't already tell, I'm a big advocate of buying nutrients based on their value and not on their marketing or popularity. I am willing to try new stuff, because I can afford to and it's actually fun for me. However, I think a lot of new growers waste to much money adding this and that without really thinking about what's in the bottles. I waste money too, but at least I know I'm wasting money at the time of sale.
