In before 777driver

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I traded in both, and yes I believe the anaconda is better than the T9 in terms of profits per hour. It is actually not so easy to see why, because it has 468 T cargo shieldless, vs T9's 532 T, so about 12% less. But:
(a) It is faster and more maneuverable, so you can get in and out of the mailslot, and out of station masslock range faster.
(b) It has bigger jump range fully loaded. Mine does over 20 ly, whereas the T9 can only do 13 ly. What this means is that for many routes that take T9 two jumps, the anaconda can do them in one. On any route where the anaconda saves a jump vs a T9, it is much better.
(c) Because of the jump range issues, there are some routes that are only available to anacondas and no other ships. For example, I am currently doing a route where the stars are 35 ly apart, with a turnaround profit of a bit over 2700 per ton. The anaconda can do this in two jumps one way, no other big cargo ship can. So this route is not worth it to run in any other ship. What that means is that there is less competition for these types of routes, and they take longer to run dry. Furthermore, when they do, your unladen jump range is likely 36-38 ly, so it is very easy to move to a new route. T9's unladen jump range is around 20 ly.
(d) You get interdicted far less in an anaconda, in my experience.
(e) You can do trading community goals better in an anaconda because, due to your superior jump range, a bigger volume of space is available to you for efficiently finding the right goods to bring in.
All these things add up to the anaconda generally making more per hour. The only exception is if you find a route no one else knows about between two stars <13 ly from each other. Then the T9 will pull ahead (but by less than 12% because it is slower and will thus run a bit less of the back-and-forth trips per hour).
For myself, I don't know any secret T9 routes, and in my experience any good route gets found out fairly quickly via crowdsourcing. The anaconda gives you much more flexibility for choosing routes to run, you can stay in a particular route much longer (because most traders still don't have anacondas to compete with you), and on average you make more just due to speed and jump savings.
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Once you have the anaconda kitted for trading, and can find a route that gives you 6 million per hour, you can earn the python in:
(55171395 - 55171395 * 0.16) / 6000000 =~ about 8 hours of trading.