Suggestions needed re Independent schools in Reading

[VegVolcano]

Hi all,
I am in need of suggestions here re some good independent schools in Reading. DS is 4ys and would go in 2017 reception class. He has been going to another independent school for a year in the nursery class. I am looking at schools in and around central Reading and have listed down Crosfield and St. Joseph. Crosfield looks slightly costlier than St Joseph. Is it worth it? It also says they interview/assess little ones. Is it true? how extensive is the assessment?