Too many counters

[Destore117]

If {Æther vial} gets too many counters can you not use it anymore? (Accidentally putting too many like a noob) Or can you put cards with less than the number of counters?

[Lyriczulu]

Since it specifically states "with converted mana cost equal to the number of charge counters" you can't put a creature on the battlefield unless it has the same CMC as counters.