Both are very popular for this engine, presuming its a D4D.
Have you considered doing an exhaust first before the chip?
After trailing some forums the general consensus was it makes a bigger difference than the chip alone, idealy do both at the same time so the chip can be calibrated to suit.
The difference is staggering.
I have fitted one to my Prado and its made a massive difference. Turbo spools up a lot earlier, heaps more torque and does not drop off as much and fuel economy is much improved and tows so much better.
I also run a K+N filter which also made a difference.
I run a beaudesert system with a ceramic coated dump pipe. Its a bolt on system as the hilux one would also be.
Both DP and Steinbeuer are not cheap but are both widely used for the common rail Diesel.
So i would say 6/half dozen.
Might be worth jumping on a forum like newhilux for a read.
And Welcome to Myswag!
Hope this help.
Cheers BD