I whole heartedly agree with Alec's point about the hilux quite possibly being a better daily driver for the reasons he gave.
I've not owned a hilux but I drove an 80 series landcruiser for 7 years as a daily, in Melbourne traffic and found it perfectly fine - but NOT as good as the lighter (smaller) IFS units that my mates had but once I changed the drivers seat to a recaro this was not a problem at all.
Your mechanics advice while well meant, was off the mark I recon. The 1HZ will handle turbo'ing with ease ... I put mine on at approx 125,000k's and was sensible with the boost plus changed the engine oil and filter every 5,000k's for the next 200,000k's trouble free I owned it.
Looking at the two vehicles though if the landcruiser is still naturally aspirated the price difference is more than $3k.
What I put on mine and if budget allowes I'd recomend anyone to do the same given the massive difference the combination made was:
3" mandrel bent system (most off the shelf units have a 2.5" dump pipe due to space restrictions and I had an engineer mate redo to as 3" from the waste gate whhich required a wedge or shim and additional bending but the increase in torque as noticable ..... you want the most space where the gasses are hottest),
fuel compensator on the pump - the factory turbos all come with this and after fitting it I could see why (you may well do a pump rebuild so the cost can climb FAST.
I did each of these one stage at a time in the order listed above, each was a ripping improvement on their own however combined they we great ..... and very expensive, at the end of it all I still the same old heavy 80 all be it a better performer that owed me a truckload more than it did at the start.
I think be as frank with yourself as to where most of your diving will be and with regards the offroad times do you need a 'strong' car or will a really capable one do in most circumstances and then spend accordingly.
Sorry about the rant .... I'm getting old.