Unless your LFS charges an arm and a leg for it or is really far away, I would definitely say yes. My LFS is literally 1 light down from my house and sells pre-mixed salt/RO Water for 75 cents a gallon and regular RO is free (which is used for topping off the tank). I know in the long run it is still a bit more expensive than an RODI system, but honestly the hassle factor for me just doesn't make one worth it at this point. My tank is 36 gallons and I do about a 10 gallon water change every 2 weeks (until my Protein Skimmer arrives). The problem with an RODI system, outside of the initial cost is that you always have to keep in mind that you produce about 3-4 gallons of wastewater for every good gallon of RODI and the process takes hours to produce even 10 gallons worth. This is to say nothing of the hoses rolling garbage cans, etc. required for the process. For a guy with little kids it simply isn't practical. And having to only lug 2 5 gallon jugs a short distance isn't a big deal either. It's just a matter of figuring out what makes the most sense to you.would it be worth it to just get ready made saltwater for now and then make my own for water changes