When you think of Bushman, Ohana, Kala, etc... think Blueridge guitars. They are Asian made instruments that sound and look prettty decent, but don't quite hit the mark of Martin, Gibson, or Taylor. Then again, you're not paying top dollar for them. I have two KoAlohas, and an Ohana. There is just no cpmparison in overall quality. The Ohana is a nice uke and feels a niche, but a nice Martin tenor would fit the bill much better.
When you think Martin, Gibson, Taylor, think KoAloha, Kamaka, Kanilea, etc... As far as custom builders, thing Glyph Ukuleles, Andy Powers, and even some from the ones named above.
Interestingly, the latest ukes from Martin haven't gotten rave reviews. The 5K and the Daisy are outstanding, but the new style 3's are getting mixed reviews. I think the issue is, they are being compared to Vintage Martins, and that probably just isn't fair. Martin isn't really set up to do ukes the way they used to, at least not finish wise. The build quality is good, but the finish they use today is much different from the ukes of yesteryear.
Kiwaya is another mass production builder who build really nice sopranos and concerts. Very much like Vintage Martins in both build and tone.