I am a firm believer in the 20* setup. I have found that on those hot summer nights I don't use a UQ at all and my 20 degree tq is easy to just throw off of myself if I get a little warm. When it gets down below the 60s overnight the 20* uq is not bad and can be hung loosely to allow some air between yourself and the quilt. Also, you can always vent the tq as well. Just a lot more versatility with the 20* and no concerns during the winter.
Those who speak don't know, those who know don't speak.
“They deem me mad because I will not sell my days for gold; and I deem them mad because they think my days have a price. ” ― Khalil Gibran