The act of fitting fat muddies has long been a common modification for 4x4 owners 

Pros

• Increased Ground Clearance 
• More sidewall for a softer ride
• Better Approach and Departure Angle 
• Looks Sick 

Cons

• Heavier
• Taxes Power
• Messes With Speedo (speeding fines inbound)
• Lifts Your Centre of Gravity
• Worse fuel Economy 
• Need Supporting Modifications to Provide Clearance

To fit 33's on a N70 Hilux you will need to do the following modifications

1. 2 inch lift
2. Relocate water washer bottle
3. Peen or hammer the body seam flush
4. wheel alignment, moving the lower control arms out at the back and in at the front, 
5. then adjust toe with steering tie rod
6. Front Body mount chop/delete Available here

Final thoughts

Yes, there are a few negative sides, However

you cant tell me they don't look sick.