I'm sorry, but I didn't think either of these episodes were particularly good. Mermaid Man Begins barely made sense and actually contradicted some of the stuff we knew about MM&BB from previous episodes and Plankton's Good Eye was just plain weird and grossed me out a little.
Neither of these episodes were bad by any means - they certainly don't reach the lows of Squidward's School for Grownups - but I've come to expect better from season 8.