I like both, and which depends on my mood.
I prefer British tea brands and select from specific growing areas or from blends I like.
My tea brands are Twining's and Taylor's of Harrogate.
In a Darjeeling, I prefer the Taylor's, as it's a fuller, stronger example of the type. In Ceylon, the two brands are virtually identical.
Taylor's sells a good Assam here but I don't think Twining's exports their Assam teas here.
Excellent blended teas, sourced from more than one area, include Twining's Irish Breakfast and Taylor's Yorkshire Gold.
You'll probably have to order Taylor's teas Online. Amazon stocks a few, but Taylor's have their own US site.
Twining's, founded in 1706, supplies the Queen. Taylor's holds the Royal Warrant as supplier to Charles, Prince of Wales, heir to the Throne. Both firms provide excellent tea.