When was this? It's kind of hearsay but I've heard of issues.... I'm not anti the product I'm just interested... I've had a Lebanese client refuse one saying it's not allowed and I figured it might, sadly, be the case.
Well I've had a G100 in Beirut several times hassle free. The Lebanese have no issues with the IAI built aircraft now. I'm based close to the ME and go to varied destinations in and around the region such as Lebanon, Jordan, Qatar, Dubai, Yemen, Israel, Egypt etc. without issue. Saudi overflight is also not an issue but I don't know about AOG parts if stuck in Riyadh.
As far as Syria, we no longer overfly the country. It's not allowed, I don't believe you will get overflight permission. We used to years ago, but no longer do.
The G150 is a great aircraft with baggage space a Hawker driver could only dream of. .85 Mmo pretty respectable too, even although a G100 can cruise at that with its .875 Mmo.
The FSI DFW guys have plenty of time on the aircraft so know it's quirks well for initial training. In Europe you have Columbia in Germany and Altenrhein in Switzerland for maintenance. Agreed, the flap/slat system can be problematic for some. The de-ice boots are hardly ever used, the wing does not pick up ice often. Make sure you get a good pre-buy.
Also, there are a fair few IAI G200's based in DXB - obviously not an issue for their Arab owners.
The G150 only has a Gulfstream data plate, as do some G100's.