I have not done any controlled tests, but once I started using Whiteside bits, I don't buy anything else unless I'm in a pinch and just run to the big box and pick up whatever works. Whiteside just seem to be sharper and last longer than anything else I've tried. I have their 3 3/8 diameter panel raiser and their rail and stile pair. I've used them for a couple dozen raised panel doors and drawer fronts with no noticeable loss of performance. But these are the only raised panel and rail/stile cutters I've ever tried. I've seen a few magazine tests that showed them to be the best among those they tested. The rail and stile pair are not length-matched like the Sommerfelds, but I get past that with 2 dedicated routers & plates that I just swap back and forth in the table. Never miss an opportunity to buy another router! You can get a good one for the price of that trio of bits.
“We should be careful to get out of an experience only the wisdom that is in it and stop there lest we be like the cat that sits down on a hot stove lid. She will never sit down on a hot stove lid again and that is well but also she will never sit down on a cold one anymore.” - Mark Twain