I am currently using the RO Buddie and use the inline TDS meter at some point I'm sure I'll pickup the Booster pump for the fact I don't like waiting hours for water to be filtered.
I have had the 4 stage 75GPD BRS Unit for about 5-6 years and its been amazing. I keep a 32g brute topped off and have had no need to look for something better. Just upgraded to a 65 gallon tank, and I still dont think I will need anything larger as I hope I don't have to do any 50% water changes. Also the 75GPD fills a bit faster than that I can fill my 32G brute in about 6-8 hours. Making the flow closer to 150GPD (not sure if thats an issue but my water comes out 0TDS although I do have high pressure 85PSI)
I'm a big fan of the products offered by www.buckeyehydro.com They are a great company with a very competitive price for their equipment. They also have the very best customer service of any company that I've dealt with.
I've had their 75gpd 4 stage for at least 10 years. Other than normal filter and DI changes it has never had any issue at all.