I voted no. Mainly because I see no reason to change the sounds in particular when the entirety of HL1 is dated. Modernizing the sounds whilst leaving, for instance, the graphics untouched seems pointless. I say keep it as kitsch and classic as the narrative allows it.
But! If you do keep the new sounds (which won't make me or anyone else stop watching, I'm sure), I merely request an extra effort be made to make them consistent -- there are shots fired in the recent episode that aren't dubbed over, but were previously dubbed over for the same weapon in the same episode, which is slightly grating. An honest mistake, but one people are going to expect not being repeated if the decision to keep the new sounds is made.
Anyway, thanks for an awesome show, here's to you. Cheers!