Original Cigar Oasis: worth a try?

I have a chance to buy a decent 150-200 count tower/drawers style humidor and it comes with the original Cigar Oasis. I know it will need a refill, so:

1 - are refills for the original still available? a) Same refilss as for the newer models?

2 - The newer models have digital readouts, which aren't exact anyway, so, is there any reason to shy away from the original? What are its drawbacks?

3 - can this original be calibrated?

thanks everyone