tKF,
In a helo, is losing the ASI as serious as it would be in a FW aircraft?
No. On the whole, airspeed isn't crucial in a helicopter. Helicopters don't stall at low airspeeds. At very low airspeeds, with a rate of descent and power applied, it is possible to get into Vortex Ring, which roughly means you descend in an uncontrolled manner through your own downwash...and fall out of the sky if you don't catch it in time. However you need less than 30kts airspeed for this to happen, and it would be unlikely even with a dodgy ASI. If I lost the ASI in a helicopter I think I'd just use outside references and my other instruments, and carry on as normal. If I couldn't fly in VMC I'd land, but I'd do that anyway.