Im definitely no mechanic but having had a 08 trafic and 2013 transit I would go for the trafic out of the two.
The trafic was ex aa and the only problem I had in 3 years were the injectors. One of them went at around 90k but luckily wasn’t stuck in the head. Had all 4 replaced for £1500.
The problem apparently is caused by water getting down around the bottom of the windscreen somehow and pooling around the injector. The is a very easy fix if you have a google.
I wouldn’t touch another transit with a barge pole. Had numerous faults with stop start, dpf, egr valve failing. Injector went at 90k.
Rust was shocking as well for a five year old van.