Good low Cost Reverse Osmosis Water Filter?

Is this 5 stage any good? 50 gallons a day.
http://www.ebay.com/itm/like/142041081146?lpid=82&chn=ps&ul_noapp=true

Or this 3 stage?
http://www.ebay.com/itm/Complete-3-Stage-Black-Countertop-Undersink-Water-Filter-System/252543444082?_trksid=p2141725.c100338.m3726&_trkparms=aid=222007&algo=SIC.MBE&ao=1&asc=20150313114020&meid=e70edc695d5b45f6935c9f22e8f5677e&pid=100338&rk=11&rkt=29&sd=142041081146

I have well water and it seems to be pretty good but one of my cronies said to add a filter.

Thanks for any help "homies."

I got a 150gpd for around $70 from pure water club . com. I upgraded it to a 300gpd for another $70 or so last year.

50gpd isn't very much, depending on our res size. The 150gpd took around 45-1hr for 5 gallons

Cheapest I've found and work great. I Replace filters every 6 months or so.