My personal opinion (yeah, I know, no body asked for it, but I just can't help myself (pestering addiction)) is if they are similar, there won't be any difference. But if there are major design differences, such as better power supply, bigger transistors, etc. that there will probably be a difference if more power / headroom is available, and is being used.

https://docs.google.com/spreadsheet/ccc?...amp;usp=sharing