I ran a flight school at LNK for a few years and utilized Silverhawk for some maintenance plus fuel. They weren't the best partner (wanted to see us disappear, complicated airport politics). My experiences with them back then would be totally irrelevant today (mostly different people, plus they sold, or gave up on the FBO & maintenance side to focus on charter).
Above situation aside, I knew quite a few pilots that worked for them. Seemed like they flew nicely maintained airplanes and had a good safety culture. I never saw their pilots doing anything I would consider risky. The only complaints I heard from their pilots was related to the pay. Most folks moved onto the airlines or better paying charter/corporate after a few years. The pay situation is probably totally different today. If you're happy with what they're paying you, I'd say go for it, the asks from them will be reasonable and you won't be flying junk.
As an instructor in the area, I really appreciated their charter pilots, as they were constantly doing flights. I could always chat up a pilot that just arrived to get the latest on icing conditions and tops.
Anyhow, no longer live in Nebraska. I moved to Wisconsin earlier this year.