I've personally been using contact lenses for more than 15 years and I have used all the brands you have named. All of them are the same when you compare the solution.
Aqua soft is the most economical but the nozzle is not very good and the solution does not flow out smoothly. Optifree is the most expensive but the bottle is more user friendly as there is free flow of the solution. Renu free is somewhere in between in this regard. Also, a patient once told me that the transparent bottle of Renu is very useful after the solution finishes. After washing the bottle thoroughly, he used it for dispensing cooking oil! It's very handy as the oil comes out on squeezing the bottle.
What is more important is the hygienic way in which you handle the contact lenses. Always wash your hands with soap before application and removal of the lenses. Don't sleep with the lenses on.
You an try using renu fresh or aqua soft solution which are available in the market...opti fresh is also good enough...these are nothing but various brands...you can use which ever is convenient to you...anything would do fine... thank you