If you're using MADI out from a desk, you're always going to be dependent on the reliability of that MADI source. You could split it at the desk to two cables, which means if you have one bad cable you're covered. But if it's clocking you're concerned about, any clock weirdness will end up in both lines.
But I did a bunch of shows last year recording MADI straight from the FOH desk without any trouble. If it's working during soundcheck it tends to stay working for the show. Although, come to think of it, I did have a problem a couple of years back when recording from a Digico D5 (turns out the desk's clock was running too fast, caused dropouts).
For gigs where I'm flying out and limited on what I can carry, I'm about to start using a JoeCo BBR64-MADI as a safety recorder. It's quite suited for that sort of thing - 1U high, light weight, and self-contained. Needs no screen or keyboard. Downside is it's relatively expensive. Main system is MBP + Madiface etc. Can let you know how the JoeCo works out.
I'd rather take my pair of custom PCs with RME cards in them, which I know are rock-solid, but that's 10U and probably 40-50kg. For reliability and control over everything, I'd always prefer to do an analog split and use my own preamps etc, even if I'm recording to MADI. But circumstances and budgets are tending to dictate the kit I can use.
At one show last year I turned up with my laptop and RME interfaces and the FOH engineer asked me where I had parked my recording truck! It never fails to amaze/dismay me how big a chasm there is between the band's budget and the TV sound budget.