This bra is a very good bra under almost anything, including anything you could wear a 4510 under and a few shirts with lower plunges (the center gore is a bit shorter) or with alternate necklines like halters or racerbacks, due to the convertible straps.
Much like the 4510, this bra is very simple, basic, and unadorned. The nude works well under everything. It is the same kind of molded cup, with a slighly plunging cup rather than the standard balconette style. In a pinch, it can be worn as a strapless, though I wouldn't recommend it for long periods of time, as it really doesn't have the staying power the 4530 does. It gives the same kind of forward, rounded shaping as the 4510, with a great support to pull breast tissue forward from under the arms. A great go-to, everyday kind of bra that works great with necklines the 4510 just can't handle.
The band is VERY stretchy. Right from the start, I can hook the band on the tightest hook and it is still too big. The wires are too wide for me. The gore doesn't tack but that's because the band is too big, I think. The straps are also VERY stretchy. They are as tight as they can be and aren't short enough. This may be because they are convertible - the straps need to be longer to accommodate the criss-cross option. So I tried it on with the straps crossed, and it is definitely better with the straps. But the cups have serious quadding and the gore is floating farther away so the cups are just not right. If the cups were right, I would keep this bra (or order it in a 32 band) and wear it criss-crossed because it seems very comfortable that way.
I like this model overall, but it's too small in the cups and too big in the band now. It's held up quite well to a lot of wear, though, and I consider that I've gotten my money's worth out of it before I sized out of it. The band does seem to stretch out quite a lot when it breaks in, though, so keep that in mind.
I love the overall shape of this model of bra, and the options for how to wear the straps (made me very sad when they discontinued it) but this particular size just doesn't fit at all in the cups. I have another in a different size that did fit for a while and it's held up very well.