I have used two stains, Solar Lux and a concentrate. Both strip and sng. One thinned with alcohol and one with water. The water based was much easier and safer to work with. Be careful to stain before any panels are scarfed on SNG. Have not noticed any swirl marks but there may be some minor ones. I used two coats of a red stain with the last boat. Be carful not to get too dark or you may not see the wood grain.
Sanding always seemed easy. Wetting out to raise the grain and highlighting the problems works great. IMO
Had one boat sanded and stained and then had a pipe condensate and drip a couple drops onto the deck. It left spots but I was able to touch it up prior to glass. Do have some extra strain drips under the epoxy on my Yukon from a touch up near the stern....