You know, that is a great question. Never thought about it because I think all our minds have been stuck on the first step alone, first. And that's if even stealth-shaped aircraft can be picked up on radar to begin with. So while concentrating on that technological step, we haven't given any thought to the next step which is what you just mentioned. Now that you raised the important question, we'll have to look into it and find out if it's only picking up the target but then what? How do you lock onto it and what mode are you in when you're actually battling the stealth feature while trying to guide either an A2A or a G2A missile.
Mmmmm.....very interesting! Now that you mentioned that particular type of surface to air missile system, it makes all the sense in the world that Egypt went out and bought it! I'm sure you know that Egypt acquire the German IRIST-T-SL system and with the Russian super radars -- particularly the Resonance-SE -- once a stealthy aircraft is detected, the radar is probably commanded to signal specifically the IRIS-T missiles. It makes all the sense in the world. At first we were like wait, they bought the Kub, the Tor, S-300, and they have a whole slew of other preceding systems like the Pechora, Avenger even the Patriot (we think the latter is set up in Cairo and certain valuable areas that have been worked out with the US) and other systems and right after they bought a bunch of the S-300VM batteries, they went out and bought the IRIS-T SL and we were like "wuuut?" Now that you mentioned its effectiveness to target and track stealthy aircraft, it makes sense why they got it.
Usually they distinguish SAM systems by batteries, but the IRIS-T SL was by systems and according to Wiki, Egypt bought 7 systems which include the guided missile truck and the multi-mission radar.
That's great. I have been reading a little bit about how the X-band radar is becoming the one that's best suited for picking up stealthy targets and it's clearly that way in that picture chart. IIRC, Russians have been touting the X-band radars as the new type they'll be building for their upcoming radars.