Unless your soff cut guy sucks, then it's noticeable.
Don't pour anything right now (winter in gen unless you have to) especially stained concrete. Sure you can blanket it, but on something like that don't take chances. If you are wanting some type of curve on the patio, don't let your concrete guy cheap out and use 2x4's to round the edges out then go back and try to fill the curve with concrete. Make sure they use metal flex forms. We just cut up/removed/re-poured a $8,000 stained patio that the original guy fugged up big time. He got the pattern down good, but that's about all he did right. Definitly get someone who has done this before, and doesn't talk big game/small price. Do it once right, even if you have to pay alittle more. You'll be happier in the end.