Land Rovers aren't for everyone
In the end, if you have serious doubts about owning a Land Rover, then don't get one. I know people who swear by the marque, others who swear at it. This is the case for each marque, not just Land Rover. Each car has it's own foibles. Here is a quick run down.
The Patrol is a 2WD on bitumen and is a copy the 1972 Range Rover suspension design / setup, without self leveling on the back. The engine is known to detonate - IIRC something about the engine running too rich, causing high EGT, due to a faulty sensor (others may be bothered to look up what the cause is). Poor back suspension for loads - the rear springs aren't supported enough by the chassis, leading to the top housing cracking and failing - a mod is available. Rugged transmission setup. More accessories are available, new and secondhand.
Landcruiser - firstly need to pay the Toyota 'tax', due to the perception that they are built better. D4D engines are failing; Diesel V8s have had oil consumption problems in the past (now fixed?). Older diesels are old technology (chamber based injection), so oil changes every 5000km, unless you are driving it in extreme conditions (stop start traffic, off roading, short runs etc) when it drops down to 2000km between oil changes. Need to flush the oil to get rid of the carbon build up, otherwise the oil turns black after startup or within 100 km or so. Poor fuel economy for the power output on the new engines; Poor fuel economy and performance on older vehicles. Parts are a bit cheaper (? don't know if this true, but the Toyota parts that I have bought are reasonably priced, with lots of Chinese copies available) and more available for the older engines. Transmission is weak, but later models are AWD on the road, so better handling. Suspension is rugged, although also a copy the 1972 Range Rover suspension design / setup, without self leveling on the back. More accessories are available, new and secondhand. Great as tow vehicle. New Landcruisers have their own postcode, due to their size. Prados - failure (cracks) in the firewalls if a bullbar is fitted, cracked dashboards are common experiences. (Prados aren't really a Landcruiser though).
Discovery - oil in the ecu, fuel pressure regulator may leak, oil bolt issues in older engines and other known issues. More sophisicated than Jap contemporaries (perhaps with exception of Jackaroo and Pajero to a certain extent), so appears to be more fragile, as more parts to fail. From 1999, twin airbags, traction control, hill descent control etc on base models. Parts may be more expensive (unless bought from the UK), AWD on the road, so better handling. Better fuel economy, better handling for those with ACE and better suspension for those with SLS.
Pajero - torsion bar front suspension, so limited off road travel, but only needed in extreme circumstances. More car like, has TC and ABS as standard in early 2000's; ESC from 2004 (?). Rugged rear diff. Fuel economy on par with Discos. Bigger 4 cylinder diesel for similar power output.
So that's my next 2c worth, which when rounded down ....