For long term reliability, go with the Tundra!  I’d definitely avoid the Ford F-150 V8 for MY 2018 and later.  Please see post below from one of our esteemed members Mod_Man.

The new Gen3 5.0 Coyote V8s are susceptible to oil consumption due to Ford switching to plasma arc cylinder liner technology.  In 2021 MY, those engines came with cylinder deactivation which will wear out/damage your engine over time.  Also, the 10-speed AT has had some issues and still not true and tried yet.  

https://carkiller.com/scottykilmer/qa/2018-ford-mustang-5-0l-questions/

No contest, go for the Tundra.

Tundra

Experience from an owner of a V8 F-150

@mod_man :

"... I just finished suing Ford Motor Company last year over my brand new 2019 F-150 with the 5.0L. The thing fell apart almost immediately. I also owned 2 Mustangs with the 5.0L and 10 speed trans...an '18 with and a '19 Cali Special. I babied both. Both developed the tick, both consumed oil. When I say they consumed oil, I don't mean they "sipped" oil. I mean they were drinking a quart every 1,000 miles. 

My F-150 had 6k miles on it and was 9 months old when I finally won my lawsuit and returned it. Both my Mustangs had under 10k on them as I was using them for show pieces here at my shop. No track time, never drag raced, just driven to the shop and back home.

Those Coyote 5.0's have a huge issue: Ford decided NOT to use steel sleeves for the pistons and instead used a crappy spray in liner that fails. It was being used on the Shelby models for years with success. However, those were limited production. When they started using that process on mass-produced vehicles, the quality dipped and all kinds of wonderful things started to happen. I actually had liquid oil from the motor blowing out both my tailpipes. How that is possible, I do not know. I also noticed the car ate coolant like mad but never leaked or overheated.

I drive a Honda now and will never own another Ford....nor will my friends and family."

Tundra. Hands down. 

that's a significant difference in price isn't it?

I say Tundra, for sure! Comment, though: … here in Calgary, these trucks are currently being substantially discounted - off list, if you paying cash. Not sure what’s the story like in Victoria. So, … I would try pretty darn hard to get the price down. Mind you, we have six Toyota dealers in town, … plus a seventh, 40 kilometres down a ‘pike going west!

F.S.