I have had my Hydra about 2-3 months and my CO about 2 years. This is my report on how they compare.
Hydra:
One problem with it going haywire but a simple reset and it's worked flawlwssly.
Adjustable easily adjusted to control humidity a big plus
Digital hygometer read out that is also adjustable a big plus
Extra fans a big plus
If the power goes off it turns off the unit and you must turn it back on and reset unit a small problem
Only one size a small problem I'd bet they build a bigger unit in the future
CO:
I had to return the first two but the one I have now has worked flawlessly since.
Not as easily adjusted but when you get it "set" it stays "set" nuetral
No hygrometer nuetral
No extra fans a small problem
If the power goes off it stays "set" when power comes back on a small plus
Bigger sizes a big plus
I use Super Absorbant Polymers in the CO and will in the Hydra when the foam needs replaced (instead of buying another cartridge). I also use SAPs in my Set n Forget. I have K/L in the coolers with the Hydra and Climaxx Beads (same as Heartfelt beads) with the CO mainly to keep them seasoned to switch out in my desktops as needed. I do think they help stablize the humidity but in a cooler this is probably over kill. Both will work to season a new humidor (I have seasoned desktops and small cabinets) and season K/L & Beads
Over all I like the Hydra better in fact I bought a second for my third 150qt cooler. If it lasts as long as the CO it's a hands down winner. If you need a little more air movement/humidty the a CO with it's bigger unit is probably the answer. I chose these as I don't want to use PG or any other chemicals and have had no mold problems (knock on wood). I know some have added a few drops of everclear/grain alcohol to the SAP's to prevent mold but they are cheap and lasted 2 years so I see no need.
This is just my experience. As always use whatever works for you and whatever you feel comfortable using.
Hydra:
One problem with it going haywire but a simple reset and it's worked flawlwssly.
Adjustable easily adjusted to control humidity a big plus
Digital hygometer read out that is also adjustable a big plus
Extra fans a big plus
If the power goes off it turns off the unit and you must turn it back on and reset unit a small problem
Only one size a small problem I'd bet they build a bigger unit in the future
CO:
I had to return the first two but the one I have now has worked flawlessly since.
Not as easily adjusted but when you get it "set" it stays "set" nuetral
No hygrometer nuetral
No extra fans a small problem
If the power goes off it stays "set" when power comes back on a small plus
Bigger sizes a big plus
I use Super Absorbant Polymers in the CO and will in the Hydra when the foam needs replaced (instead of buying another cartridge). I also use SAPs in my Set n Forget. I have K/L in the coolers with the Hydra and Climaxx Beads (same as Heartfelt beads) with the CO mainly to keep them seasoned to switch out in my desktops as needed. I do think they help stablize the humidity but in a cooler this is probably over kill. Both will work to season a new humidor (I have seasoned desktops and small cabinets) and season K/L & Beads
Over all I like the Hydra better in fact I bought a second for my third 150qt cooler. If it lasts as long as the CO it's a hands down winner. If you need a little more air movement/humidty the a CO with it's bigger unit is probably the answer. I chose these as I don't want to use PG or any other chemicals and have had no mold problems (knock on wood). I know some have added a few drops of everclear/grain alcohol to the SAP's to prevent mold but they are cheap and lasted 2 years so I see no need.
This is just my experience. As always use whatever works for you and whatever you feel comfortable using.
