Holding in an Oven vs Sham

I can't speak to the Alto Shaam, but many backyarders use their ovens for extended "active" holds. However, it should be known that oven temps can vary greatly from their set temp...some more so than others. Say you set it at 160*, but maybe there's a 20* +/- fluctuation above and below the set or average temp. As long as your food tolerates any oscillation like that, or the oscillation is small, then I don't see how there'd be any problem.

You only need to hold at 135, 140/145 if you dont trust the thermostat, and most ovens aren't meant to hold that temp, an alto sham is. In a pinch for shorter periods of time an oven will work, but they aren't ideal.