I'll just add that I fed Zupreem Natural pellets for a couple of years, then about a year ago I switched all 4 of my guys (Senegal, Green Cheek, Quaker, Cockatiel) to both the Tropican pellets (all of the eat the Conure size in your link except for the Senegal, he eats the next larger size up), as well as the Tropimix seed-mix for medium parrots, which doesn't contain any sunflower seeds or peanuts (or other nuts/fatty seeds), and also contains the Tropican pellets in it as well, so they actually get the Tropican pellets as a part of their seed-mix too, which has worked very well. They all love them, as they are flavored with natural fruit and veggie flavors, and the sugar is still low/on-par with other Natural pellets, but they still love them...The Tropican pellets and the Tropimix seed-mix both smell exactly like JuicyFruit gum to me, lol, and they love it. Their feathers are great, their molts go smoothly and quickly, their feathers are shiny, and all 4 of the actually gained a bit of weight, which my CAV was thrilled about, especially my Cockatiel, who barely ate any of the Zupreem Natural or the Harrison's, which I tried first before the Zupreem, and I paid for 2 months worth of it and they just didn't like it, so I stopped spending that money and went to the Zupreem Natural, which they liked, but it contains some ingredients that I don't like, and since my CAV told me to either choose Tops or Tropican, I chose the Tropican for 3 reasons: #1 Their Tropimix seed-mix is awesome, it's healthy, varied, and most importantly contains the Tropican pellets in it as well, so they kind of get tricked into eating more of their pellets after they've already gotten their pellets (I am one who feeds a small amount of a healthy seed-mix to all of them every single day, as it's natural and healthy for both their bodies and minds to eat seeds), #2 It's available in a pinch locally at Petco, in case I run out and haven't gotten my order from online (both the Tropican pellets and the Tropimix seed-mix are available at any Petco at any time), and #3 it's much, much cheaper than the Tops...So Tropican pellets with Tropimix seed-mix has been by-far the best choice of pellets and seeds for my birds, and I don't see myself changing ever again...
****I would NOT feed your birds the "Nutribird", as it's the only low-quality, sub-standard pellet/seed-mix company that you listed; both their pellets and their available seed-mixes contain lots of sugar, fat, and many harmful preservatives that are known to cause health issues in birds...If cost is a concern to you but you still need to choose a high-quality pellet and/or seed-mix for your birds, as well as one that they are extremely likely to eat and love, I'd absolutely recommend that you go with the Tropican pellets, and if you want a low-fat, fortified, healthy seed-mix without sunflower seeds, nuts, etc., their Tropimix seed-mix that also contains the Tropican pellets in it. Not only are they right on-par with Tops, Zupreem, or Harrison's as far as nutrition and ingredients, but they are the only available parrot pellet that I'm aware of that contain the overall-nutrition, low-fat content, and low-sugar content of the "Natural" pellets, so they are basically a "Natural" pellet nutrition-wise, they still are naturally-flavored with vegetable and fruit juices, so the birds absolutely love them. I had no problem at all switching all 4 of my guys over, and if my female Cockatiel, Duff, will willingly eat a pellet, then you know it's good! Duff has fought me on EVERY SINGLE PELLET I've ever brought home to her, and I'm not ashamed to admit that I actually bought a small sample-bag of Zupreem "Fruit-Flavored" pellets out of desperation, which she turned her beak right up at too! I actually gave-up and was simply feeding the Zupreem Natural pellets to my Green Cheek, my Quaker, and my Senegal, and at that time I was feeding Higgins VitaPrima California-Blend seed-mix, so I just fed Duff the healthy seed-mix and that was it, I gave-up on feeding her any pellets at all...HOWEVER, when I made the switch from Zupreem Natural pellets/Higgins VitaPrima California Blend seed-mix to the Tropican pellets and the Tropimix seed-mix, which also contains Tropican pellets in it, I saw Duff actually eating the Tropican pellets that were in the seed-mix!!!! On the first try!!! So I gave her an entire dish of pellets, and low and behold she gobbled them all up throughout the day!!! So I owe Tropican pellets/Tropimix seed-mix my sanity...no joke!
