I actually really like this episode (I say like because I have watched it quite often. It is in my top five list of season 5 episodes). I found a lot of humor in it, and I really like that SpongeBob is kind of an egotistical jerk, and in general, I love how he's capable of lying about this stuff to make himself look better.
I think this episode is really great and pretty funny. I'd actually be up for giving it a 7.5/10. It had some flaws (like not really having a straightforward moral/life lesson. Which would have made sense for an episode with a lot of lying in my opinion), like a lot of episodes do, but I actually kinda think this episode is underrated.