I read a lot of "I just started an atrox engineer because everything sounds so easy now" threads, and just wanted to try to explain why it isn't as easy as it sounds.
Yes, if you have infinite resources, a highlevel main, a good guild, good friends, plenty of time, a lot of patience and know the game well, then atrox might perform just as well or better then the other breeds.
BUT, if you have only played the game a few months and want to start an engineer, do NOT chose atrox. Atrox engineers require a lot of creds and twinking to perform well when you level up. Engineers have trouble finding teams at many levels as it is, and if you get a reputation as a gimp trox engi you will most likely just give up and start an opi ma or something easy like that.
The most serious drawbacks are symbiants and armor.
Symbiants: As soli or opifex you can twink into very high ql symbiants, and equipping reasonable ql symbiants is quite easy. As trox you will most likely never equip any symbiant over ql 240. Worst part of this is the brain symbiant, as 250 is the next after 200 so you're stuck with the 200 one forever.
If you want to be a tradeskiller you miss out on a lot of points in tradeskills from not being able to use higher symbiants, and everyone miss out on points in mc/ts needed for bots.
Read this thread for a discussion on what ql symbs can be twinked in. Even the lowest ones that are referred to as "easy" are impossible for a trox to equip at this time.
Armor: If you want to wear tier armor, you will be wearing significantly lower ql then any other breed. You will only be able to wear ql300 faithful/chosen at 220 and with a few hard to get items.
Arithmetic is wearable, though still at lower ql's. Not too hard to wear ql300 at 215+ if you just camp a few items.
The main problem with ai armor is when it comes to combined. Twinking 1 ability for single ai armor is easy, twinking 2 may be very hard as the add ability items go in the same slot often. Even though you may equip ql 300 arith, you will never equip ql300 combined scouts, so you might have to settle fore ql250ish because of the sense requirement.
Here you miss out on mods from higher ql armor, and will have a harder time swapping armor for tradeskilling etc.
If you don't trust me, look at the amount of engineers of the different breeds:
Level 200-220 engineers:
Solitus: 516
Nano: 311
Opifex: 71
Atrox: 16
Atrox engineers at 200+ are a tiny group, which indicates that there are some challenges at 200+ that people find hard to overcome. Yes, it is a lot easier with sl and ai, but it's still not a walk in the park.
Engineers in general are quite expensive, and atrox engineer is even more expensive. I have spent 900mill so far, and that is not counting handmedowns from my other chars such as ncu, armor, implants, symbiants, ai items looted at earlier raids and so on.
Before you start an atrox engineer you should ask yourself these questions:
1. Do I have sl/ai?
To make a decent engi as atrox you really need sl and ai, otherwise you will not be able to cast bots and nanos that you are expected to cast at a given level.
2. Do I have the resources?
You do not need billions in the bank, but if you want to get to 200+ without giving up somewhere along the way, you should be able to gather 20-30mill on occations when you need something, and 100ish mill sometimes when you really need a piece of arithmetic armor. Getting a hold of this amount of creds as a trox engi main at tl5 and tl6 may easily take an eternity.
3. Can I accept the limitations at higher levels?
No matter what you do and how much money you have, you will never be able to equip the same ql symbiants as an opi/soli engi. In the end you will have to sacrifice a lot more then other engis if you want to selfcast bots.
If you can answer yes to those three questions, there is no reason not to roll an atrox engi. If you answer no to one or more, or you are unsure, you might want to think twice before starting your engi.
Another question overriding all others is of course: Do I want to be an atrox engi because it is fun? If that is your main goal, go ahead and start one, but don't expect it to be easy.
Personally, I only started my engi as trox because there are no 220 trox engi. If there had been one when I felt like rolling an engi, I would have chosen opi to equip extreme ql symbiants. I don't regret rolling atrox, it's quite a lot of fun, but I'll be very annoyed if someone goes on an sk-frenzy and hits 220 before me.