I would say yes, probably.
I use mine as an everyday work vehicle, family vehicle and recreational vehicle on the weekends (greenlaning etc), I bought mine with 100k on the clock, and had to put a galv chassis under her within 3 months. Im just under 135k now, and she's neve r ever let me down.
Rigorous maintenance will see you through with either vehicle, mine is remapped for lots of torque and power is around the 160bhp mark. It pulls trailers loaded up to thr gunnels very well, much better than a standard tdi could.
I must say though, whatever you choose, tdi or td5, the chassis is the most important factor to consider, if you buy one on a galv chassis, that is at least peace of mind.
The relative ease of tuneability makes the td5 a no brainer for me, also they are much more of a refined engine. Both are equally easy to spanner on in regards to self maintenance.
A cheap diagnostic tool is easy to use and in fact makes dealing with some faults easier, although I've yet to use my diagnostic kit in anger as there has literally been no need apart from to clear faults to see if they returned. It can be very interesting to use and quite fun just out of curiosity. Good luck with either, you'll have fun in both.