Eaccelerator is, in fact the most stable of the cache systems, yes.
Does it work with 5.3? I haven't heard differently, though I don't use 5.3 (yet).
The real question is Zend and ion. Both products are stalling like mad and haven't released a "stable" 5.3.x product yet, despite it being close to 2 years stable now.
Best bet? Stay away from php 5.3 for now!
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