I have Real flight via Steam.
It's been nothing but a frustrating experience since day one.
Are there any alternatives still around?

There is AeroFly 10. It seems to be geared more towards the big gassers as the biggest complaint is lack of low speed post stall behavior needed for 3D. I have both and have been spending more time in Real Flight recently. I think Steam will let you try a program for about 2 hours before the option to return it expires. I have found some planes I liked enough like the Juper Duck and Crack Folker in Aerofly to build and buy said planes. That said both sims seem to have a large number of defunct planes no longer sold. Aerofly RC is graphically up to date with Vulcan while Real Flight is half legacy 1996 windows and half sort of kind of refreshed, sort of. I don't know, if your into iMac competition Aerofly Rc might be the way to go.