I've been burnt with both expensive one's and throw away ones. It seems they all have burners that disintegrate well before they should. The difference is that the expensive one's main "body" & cooking grates are still in great shape, but you feel worse shitcaning it because it still looks good - burners shot, but it's still pretty!
I like to cook on wood now, and am converting my last burnt out (but still pretty) expensive gas grill to work with wood or charcoal. Much better flavor.
To me, a gas grill is to outdoor cooking what a microwave is to an oven. Quick, but just "ok" in results.