Haha calling hydro over rated? You just might want to check out some hydro grows. Because a good setup will give you way better results than dirt could dream of. And have fun with soil gnats.
But yeah the s&p TD 100x and a presh filter 4 x 8 will fit your needs to a t. The fan is small and quiet. And you can get both for less than 180$ shipped. But ventilation and odor control are 2 things you never want to go cheap on.
They also have the active air 4" and w/ filter it'll run about 140$ shipped. But you'll need to make a quiet box hang w/ bungie cords and only use insulated ducting and make a diy muffler by connecting your 4" exhaust to a 6" or 8" converter and run 12" of length of the wider ducting from the converter. This rapid expansion in width in the ducting will all most rid the sound of turbulence in exhaust.
But w/ your situation, I would recommend you purchase a variac speed controller for 50$-60$ to control speed. If you use the cheap ones found at shops you will eventually kill your fan and possibly catch fire when your box overheats if you don't catch it time. Variacs are the safest option and maintain fan life.
With a td100x, Phresh filter 4 x 8, and variac controller will be about 230$ again when growing you have to understand start up costs are very high. But seeing as you won't be spending 300$ for an oz anymore the price isn't bad. And you can keep the fan going for years before replacing. And the filter will last quite some time as your not passing much air through it.
Even if you spend 600 to 700 and you yield 2 oz good medication, you would have spent more buying it retail and it probably wouldn't be as good as commercial growers don't care about quality but qauntity
