There is no such thing as "stealth" aircraft if you are thinking of a device like a scifi cloaking device.
What you have is the ability to build a structure that deflects 95% of the radar energy away from bouncing back to the receiver to lower the radar cross section, and therefore an aircraft can't easily be detected at long range by "clever" radar systems. "clever" radar systems tend to give a nice neat display by filtering the information from the operator. Tiny radar returns like birds aren't displayed to make reading the display easy.
The aim of the stealth aircraft is to be squelched from the display because they look like birds and the radar return is to small.
"Stupid" radar systems like the early British chain home style WW2 style radars just displayed utterly raw information and the operator figured it all out from the display. About the best a "stealth" aircraft can do against systems like these is get somewhat closer before the operator is certain he's looking at an aircraft.
Future "clever" radars designed by people with computers available to do lots of processing work on the radar input may well go "oh look, a pigeon traveling at Mach 2? hey, maybe pigeons don't fly that fast...." and display "Pigeon doing Mach 2: possible stealth aircraft?" on the screen instead of just squelching the radar return based on it's size.
That means that you might only be detected by a radar at 50-75% of it's usual detection range, which might let you pick a path between radars without getting detected.