Yes, I've heard of them. Yes, they're reputable.
I don't have much of an opinion re: their skeleton because I'm really not "into" skeleton watches to begin with. There're only two skeleton type watches that I like aesthetically at all from among all the ones I've see so far in my life and neither of them is something worth mentioning as an alternative to the Davosa. As a result of not liking the look, I haven't put any effort into learning much about any other than the two I like.
As for the movement itself, the SW200, it's a good movement. Why Sellita's spec sheet (
http://www.sellita.ch/images/stories...3_20150226.pdf) distinguishes between Novodiac and Incabloc shock springs is beyond me for they are both made by Incabloc. The shapes are different, and presumably there's some difference in the shock protection afforded by each, but I don't know specifically what the impact of the different shapes is. (
https://watchotaku.atlassian.net/wik...ock+protection) Given that skeleton movements have less bridge structure, I presume that the more protective spring shape is the one that'd be used, but I don't know that to be so because, as I said, I don't really know what the tangible difference is between the two spring designs.
At the end of the day, I wouldn't worry about it unless I've identified multiple skeleton watches that I like and they have differing shock protection approaches. (Even then, I don't know how much I'd dwell on or research it.) I'd just keep in mind that skeleton watch movements aren't, in general, built to be as "tough" as what one might call a general use watch and adjust my usage patter for a skeleton watch accordingly. It strikes me not as something one needs to "know" a lot about, but rather as something where applying a little common sense is all that's needed.
All the best.