I own a set of jetstream and I bought a solitude jacket and bib but haven’t had the weather to wear them. I think the solitude is a nice thoughtful update to the Woodbury and sanctuary line. Good amount of insulation. Bib hand warmer pocket is a cool idea. Feels very quiet and comfortable. You aren’t going to want to walk far in them due to sweat. I sized up so I can pack the set I to the stand and then put it on over other clothes.
Sitka stratus is great. Jacket is a fleece version of the jetstream. Windblocker makes it punch above it weight for warmth but it doesn’t have a ton of insulation. Pants are great too. Both fit more or less true to size. Maybe a little loose which is fine for layering. Stand alone, I think I would be cold sitting in this below mid 40s. Sitka design is a step above in terms of refinement IMO. Better pocket execution and just a bunch of other small details that are so well thought out. To be honest, a fairer comparison for the Solitude would be the Sitka Fanatic line. Both are stand sitting whitetail pieces that will get you to the 20s or so.
I bought the solitude and am selling the jetstream for this season to try it out. I think the sitka stuff is just awesome, but it is very specialized. Due to the camo pattern and design features I couldn’t see using it for much beyond just stand hunting in hardwood. The fusion camo pattern is a bit more versatile and the design of the solitude is a bit more general. I can see wearing the solitude for things like snow machining, boreal Forrest hunting, ground ambush deer hunting, pheasant and even in a duck blind.