I would never let the lack of a particular brand's sectional curve track determine my selection.. Scale trax can be rolled perfectly to a 6" trolley radius if need be by using a rail bender. I would only use Scale trax for urban trolleys. GG can be formed nice and smooth around a plywood template. The tighter you bend any flex the more it may be best to waste cut 3" off each end to eliminate the small unbent tips.
Scale trax can stagger slide rails for smooth joint transition.
As far as cost goes Atlas is an arm and leg followed by Scale trax followed by GG. GG is the choice for good track at a great price.
Atlas O gauge track is more like G scale rail. Tall bulky, stiff to bend. However the flex length rails can be stagger slid to make curve joints blend.
Sectional curve track is the most expensive way to use any brand tack. If on a budget, bend your own and forget the limitations of diameters available,
My I suggest, DO NOT use price as a guide for switches. Trains will run on most any track selected. Once ballasted they are all rather similar. Switches are another animal altogether. Over the years I have used GG, Atlas, Scale trax, Lionel and Ross turnouts. Anymore I would only use made in the USA Ross. Period.
May I suggest to prioritize your target goal. Is it cost? Is it sectional diameter track availability? Is it the size of the rail it's self? Size of ties? Tie spacing? Tie material? Country of origin?
It sounds like you are working with a moving target.
This is something you may well need to settle on your own. Kinda like asking "Should I go to church and if so which one?" Many folks go to each church. Many do not go at all. Do what is right for you. The only way you can best decide is to get first hand experience.
Track is chosen for many different reasons. Some selections yield regret, some selections made with lack of first hand experience of exactly what is available. Other selections are ultimately replaced, that is the most expensive track scenario in both time and money.
Ambivalence is eliminated with knowledge and experience. Forum processing can be a starting point but it is only a piece of the pie, IMO