We don't even know what his TDS from tap is, if it's 500, I would say 26 is quite good.
Also, we have no idea what his RO is, if it's a 40" or a 300GPD.
Mine is a 300GPD, and I've got 100PSI after prefilters, and mine comes out at 20, in 238. I think my membranes aren't of the same quality as other purefreedom ones.
My tap water is around 480. Comes out of RO at 25 but if i let it run a few minutes it comes down to around 7.
0-5 after DI. Though mostly it is 1 or 2.
I got a bit anal about 0 tds the 1st couple of weeks of getting a RO. Couldn't get it below 1ppm.
Don't bother with that anymore though. I now change resin at 5.