Depends. If you're a Lance Corporal on the ground being attacked, there's no prettier sight than that A-10 laying down a hail of suppressive fire from that Gatling gun cannon on the nose.
The others are cool from an aviator perspective, though. Sexy, yeah, if you're a pilot.
Speaking from personal experience, if you are in contact with enemy fighters, there isNOTHINGmore Beautiful to see than an A-10 Warthog on a CAS run. ABSOLUTELY NOTHING!!!