Originally Posted by
findark
Just to try to be clear here.
Delta Comfort Plus is an Economy Class product. It features Economy Class seats with slightly more legroom and slightly better drinks and snacks. The equivalent United product is marketed as Economy Plus, and generally includes somewhat less than Delta Comfort Plus (same food and drink as normal Economy, no priority boarding, but same extra legroom).
United Premium Plus is a Premium Economy Class product, generally only offered internationally. It features different, wider seats with more pitch (roughly similar to domestic First seats) as well as plated meal service. It is a significantly better product than anything in Economy, including Delta's Comfort Plus. The Delta Premium Economy product is marketed as "Premium Select". In general, I think people find it inferior to United with slightly less well presented food and most importantly an extremely inferior 2-4-2 configuration on the A350 which is a very narrow PE product.
There will be a night and day difference between the two classes of service. Difference between the carriers can vary and may be a matter of opinion.
Excellent explanation.
One thing that can throw a monkey wrench when searching on Google Flights is that Delta's Comfort+ (which you rightly state is NOT premium economy) will come up under premium economy searches (at least for domestic flights) because Delta sells it as a different 'cabin' class. Google Flights should NOT do this, but they do.
For example, if you search EWR-LAX premium economy on Google Flights, it will show the 2 or 3 flights a day that on UA that have Premium Plus. It will also show every Delta option even though none of them have Premium Select, but they all have Comfort+. I don't know how this plays out with international searches. My memory is this problem used to happen when DL didn't haven't have many planes with Premium Select, but they have many more plans with the PS product now so I'm not sure. I never trust a result on Google Flights for Delta 'Premium Economy' and always check through Delta.com to see if it has the real product or not.