I'm doing one now as part of a larger trip and on the return (1 flight done, 5 to go as I write this from SGN), this time TUN to KUL via JED. I have found it's the long overnight layovers in JED, the unpredictable chaos of TUN, Tunis hotel overnighting due to lack of suitable positioning flights and SV regional A330 that are the down side. On the up side: SV B789 & 10 are nice, friendly inflight crew, good inflight food, good price, JED transit is easy and queue-free. This is my second and last of these routings: glad I done them for the XP and low price but also glad not to do them again.