Echo SRM 225 new owner with ?

I bought an Echo SRM 225 weed wacker. I'm an occasional user, not a pro. I just wanted a good long lasting unit. I have run 2 tanks of fuel (Echo $$blend premix) and have varied the throttle. It runs and starts better with each use. Awesome machine so far. Should I tune the carb from factory settings to improve engine life? Should I run WOT all the time? I heard they last longer and run cleaner..not clogging exhaust ports.
Thanks,
Dusty