No offense, but worrying about a turbo in today’s world is a nonissue. You far more likely to have an electrical or other non mechanical nor non terminal issue than you are a turbo issue. The folks running diesels for the last 30 years have figured this out and the ecoboost is no different. Can you lose one, sure but it certainly isn’t common otherwise these engines wouldn’t be as popular as they are. I think ford has 5 or so different size EB and GM now has a few in there stable also. As far as durability, it’s as durable as any 1/2 ton motor pulling the same duty and done might argue that they are more durable as the EB were engineered and built with many of the same principals of the Diesel engines.
As as far as a 5.0 ever running along side a 3.5 ecoboost, it’ll take far more than exhaust and an air filter, lol. Anyone that has driven and owned both can attest there’s really no comparison especially in the low end and when towing, it’s night and day. We have about a dozen ecoboost’s and maybe seven 5.0s between our fleet and personal vehicles. They’ve both been reliable thus far however I don’t think any of the 5.0s have more then about 75k miles on them. We do have 3.5 EBs pushing 175k though and have yet to have a major mechanical issue. No turbos, no motor issues, no transmission issues. Had some various electrical gremlins, a few tune ups with plug changes, some wheel bearings, a pinion bearing and seal, and probably a few other misc things. Take it for what it’s worth but worrying about the turbo would be about the last thing on my mind.