I've had my Cragars on the car for about 18 months now with no issues - but it pretty much lives in the garage. One of the other members (Nance, whose car inspired mine) has complained about rusting with his as well.
A lot of the other members have Magnums and love 'em, and then few of them (Austin Vert, MeZapU) have the wider 15x10 Magnums on theirs (rear wheels) and love 'em as well. But it seems to me that the vast majority of '71-'73s have Magnums - which is fine - they look great! I just wanted something different for mine, and decided to go 'old school restomod.'
I was originally going to go with Torque Thrust IIs (all chrome), but noticed at local car shows that almost everybody around here has 'em on just about any and every kind of car you can think of... so I decided that old school Cragars were for me.
If things ever get to the point that 15" tires are no longer available, I'll make the switch to 17s... and right now the 17" Magnums are on the short list along with Torque Thrust IIs and a couple others.