I have tx3mini 2+16gb, tx5max 4+32gb and tx3 s905x3 4+64gb.

My recommendation is bsed on what i have used.

I do not know allwinner, no comment on boxes that i have never used.

tx3mini/max works fine with astrogo but...
.. the chipset is AML s905w, a low end one, >2 years old, not many boxes using it anymore.
.. it comes in 2+16 as well as 2+8gb -  a no. of users of 2+8gb (very cheap) has complained it gets sluggish often.
.. the small higher price u pay is not just for the chipset or storage but all hardware, features and overall smoothness.
.. i find the wifi module of tx3mini quite weak.... so, unless u use ethernet or is close to router, it is not the best choice although it is dirt cheap.
.. while u may want to go as cheap as u can, keep in mind saving rm30, rm50 may give u headaches after a few weeks or months.
.. more so when u want to do more with the box.

tx5max uses a better AML chipset s905x2 and has gigabit port, ac wifi... however, this model is no longer being sold.
tx3 s905x3 is the latest model with newer AML s905x3.
can expect another tx3 model to come soon since AML s905x4 is now available.

the good news is tx3 (mini, max, s905x3) come with a simple root switch; it is easy to run astrogo.
u dun need any modified version... just get the current official apk to sideload it.
preinstalled is meaningless becos new versions come out every month or 2.. u need to update.