Eton House is fine for primary. It's a smallish school by Singapore standards, but a perfect size for someone joining from overseas.
When we moved to Singapore, I initially signed my son at Chatsworth East, but moved him to Eton House the following year. While the feees and IB system are similar, I found that Chatsworth East had too small a size to allow him to make new friends (only 2 other boys in his class), plus later I realized that he learned much more in Mandarin classes at Eton House.
Eton House also is quite good for class performances and such.
My son is now is middle school, so I have enrolled him at OFS after considering other choices. That's OT, so I'll leave it at that for now, but I would suggest you visit these two schools in the East and decide which works best for your kid(s).