I have mine both in full sun and part sun. The ones that receive sunlight only in spring and mid summer do not bloom as well as those in full sun all season long.
'Worcester Gold' keeps its color all season. I have no experience with 'Sunshine Blue'.

Worcester Gold' does reseed but not terribly so. I find one or two seedlings a year. Could be because I mulch heavily. I have not seen my 'First Choice' reseed.

Careopteris blooms rather late - toward the end of summer-early fall. They bloom for about a month or so. I have them with different companions -Allium cristophii, Geranium 'Johnson's Blue', Geranium 'Rozanne', Aster ericoides, Rudbeckia triloba, Clematis durandii. They all are bee & butterfly magnets.

I also have C. "Worchester Gold". Mine is in full sun all day long; it handles it beautifully! The foliage is always golden. It doesnt bloom terribly long, but its amazing when it does!
CMK

My Worchester Gold is in full sun and blooms profusely and holds its colour. I bought Sunshine Blue last year and was a bit disappointed. It gets a bit more shade were it is (morning sun and late day sun only). Leaf colour held but there was very little flowers. I'm going to move it this year and see if it flowers better in full sun

Sharon

I can only comment on "Bluebeard" which I have transplanted in about 4 spots in my yard (all from one shrub). I love that color blue. They would be tough to deadhead and I don't bother. Yes, it will reseed but the volunteers aren't invasive in that they'll be a nuisance immediately. They're easy to remove if you don't want any. I transplanted one to my back garden which gets afternoon sun but it does not do as well as those that get full sun. I think because by the time it peaks, the sun is starting to lose its strength in the afternoon. It's smaller and blooms less vigorously than my others, but it will still flower. I cut mine back by about two thirds in early spring when I see the new buds starting to emerge, never down to the ground. The tallest they've ever gotten up here is about 3-1/2 feet. The flowers last quite a long time and they are very hardy for me. A note of caution though - they attract bees like crazy, esp. being a late bloomer when bees are looking for pollen, so plant it where that won't bother you.

I planted the Sunshine Blue last year and loved both the foliage and the flowers, which stopped folks walking by my street corner.

But now I'm a little worried about its aggressiveness--the outside branches are rooting along the ground, and I have a host of tiny seedlings this spring. I had actually planted a group of 3 of these, only a quart size or so, and they grew enormously in the first year, so that now I have to move one or 2. But, now I don't know if I want to have it more than one place in the yard if it is going to seed everywhere.