I love this frame! It is very solid, elegant and perfect for my guest room. Assembly went smoothly doing it solo. The slats are 6” apart on the Queen-sized frame and a 10” mattress is perfect (anything thicker would cover the headboard, as will pillows a bit also). Thank you for the photo you posted, Chase from Arizona!… It helped me decide on my 10” mattress purchase! Overall, I am extremely happy with this bed frame!