Deans Ultra Plugs have been around for like forever, and have proven themselves over time to be durable and are a staple of RCers.
The Traxxass Plugs have only been out about a year, so its hard to make any durability comparisons, and like other plugs that have come and gone over the years its hard to say if they'll still be around next year or in 5 years.
Deans were initially used in the computer industry, but their 20-something year longevity in the marketplace makes them hard to go wrong as a first choice.