You don't say much about your reloading or shooting setup, so don't know what will be the best for you.
With regular access to 950, and "at your convenience" access to 1850, I would invest in the following:
- Labradar
- LR target system (don't know the brand)
- Multiple kestrel's to read the wind
And i would spend boat-loads of time shooting and reading the wind.
If you have all that, with your budget, here's the order I would buy from your list:
AMP
Autotrickler v3
Zero
Now I'll be "that guy" and piss on all of them:
I've tried to "automate" my process, doing other things while the auto feed equipment is working. It has resulted in having to hammer out brass more than once, and one KB in a pistol. Since then, I've reverted to an Amish approach - present, attentive to detail, consistent. My shooting and ammo have seen the benefits of this.
AMP : Reloading bench space is a premium for me, even though I have a 4'x5' steel air dampened microscope table to reload on, plus a 30" x 45" x 1" bare steel work bench. Putting an AMP on it is like setting a suitcase in the middle of my work. No thanks. I'm happy with my old-skool annealing techniques with gear that neatly packs away when I've done my annealing (~4x per year when I shoot as much as I'd like to).
Autotrickler :
Same goes for the Autotrickler. I have a Hornady LnL trickler and rarely use it, and it takes up a lot of space IMO. I have reverted to using a powder drop, load into the Ohaus balance scale and finish with tapping kernels out of an old lab powder spoon. Then fill case. From drop to case is about 20 seconds. Error : 0.1gr.
Other, nit-picking observations on the Autotrickler. Any time a reloader claims they throw "to the kernel" I toss that out as total BS. That aside, having built and automated scale systems, I don't agree with their design, though I'm sure it works based on the claims of others here. There's always a trade off.
Zero :
Reminds me of Sadaam Hussein's gold plated MP5, and sure would look awesome on anyone's bench. If you're working with a Lee Challenger press, yeah, get the zero. Otherwise, IMO it's a spendy "so-what". Technique is 99% of the battle.