UPD: уже нагуглил
Two key differences between LL(*) and PEG:
LL(*) can only lookahead a DFA pattern, while PEG can lookahead a recursive pattern. For example, in PEG you can lookahead nested parens while LL(*) can't.
The choice operator / in PEG is priority choice (or "possessive"), which means if you have rule A / AB, it never reaches the right hand side AB. In LL(*) for a rule A | AB, it is possible to match AB.