It depends. On the lower end of the spectrum, there are high volume products that offer somewhat better performance for just a tiny increase in cost, as mention

It depends. On the lower end of the spectrum, there are high volume products that offer somewhat better performance for just a tiny increase in cost, as mentioned in other comments. On the higher end of the spectrum there are laboratory-grade oscillators, for example the legendary Hewlett-Packard 10811 [1] and similar, which cost hundreds to thousands of dollars. These overlap in price with the lower end atomic clocks. [1] http://etoysbox.jp/Memo/3_Test_Equipments/HP_10811_OCXO/HP_10811_OCXO_Spec.html http://etoysbox.jp/Memo/3_Test_Equipments/HP_10811_OCXO/HP_1...