Well only the B4.1 works out expensive as a mid motor config. though otherwise you won't go far wrong with it.
I race the Ansmann x2c, for the money it's pretty good, not as durable as the others & a bit of chassis flex (though may make it more forgiving)
I like the idea of the DEX210 as you get mid or rear motor config. straight from the box & i believe stick or saddles fit in either config. too.
Kinda the same with the Losi/tlr 22 (saddles only i think?) built like a tank, some say tricky to set up..
Don't think you'd go far wrong with any of them tbh, all have good spares back up etc. If you race at a club, maybe see what others drive, consider the chances of trackside repair instead of no-one else around you having parts you might need, lol.
My head would say the Losi 22, my heart would say the Durango
