i got one. I paid for the 60 dollar one. It works ok for the size, pulling in an incense smoke sticks smoke all the way in from like 6 in away and filtering. I also use a 6 in htg grobrite nad a ozone filter.
If I were you I would go to bghydro and buy one of their filters and put a fan on it.
i can tell you this about charcoal filters. comapines sometimes overate their cfm rating. For instance the htg grobrite 6 in i use a 6 in 430 cfm fan on and it is too strong. A 430 duct booster would work better.
Also look for how thick the packed bed is. Also look to see if it is refillable.
For the price it would depend. A lot of growers just pull through a light hood with a filter on one end and a fan on the other. If that is the case I would go to bg hydro and get one of their filters with a packed bed and go to hid hut and get a valueline fan to match. try to get a smaller cfm. Like a 8 in filter with a 6 in fan. Or a sim price a 6 in filter and a 4 in fan. That would work best.
Or if you are useing seperate exhaust to clean air and a seperate exhaust to cool light then you can get a 100 dollare filter and a 30 dollar duct fan and you could clean all that air no prob. If you are in a tent. I noticed my duct booster attacheed to a filter can cycle all the air nad clean it. Just got get it hooled up right.