i used replenished everything. I ordered the bulk chems from unique. I have been replenishing my current batch for almost 2 years now and never had any issues. my replenished results with the fuji are far better than with the tetenal using that 1 shot. not the the tetenal was bad, just that I prefer the results from the 7 bath system. with replenishment, I wind up replenishing, with the 1st developer and color developer, about 30% of the used amount. those steps take a lot of replenishment. the other steps, not that much. I keep the stock bottles topped of with propane and the working chems and the mixed replensihed chems in air tight wine bags that are easy to fill and have the spouts that make replenishing smaller amounts easy.
maybe Im lucky, but I dont and have never used "control strips, a densitometer, pH meters etc" in my set-up. I just make sure to replenish the developers if I have not used them in over a month. keeps them fresh. first roll of every batch is a single roll to make sure the results are what I expect. your results may differ, but I prefer replenishment.
john