A little hole can still leak.
If manufactured and installed correctly, there's no more chance of a leak than with any other underwater penetrations.
For me, the real problem is cost vs. function. The good ones are several hundred dollars and up and for me, the "function" value is just a little higher than zero. They don't make the boat safer, don't make it go faster, don't save fuel, etc., it's purely cosmetic. Friends can come by and say "Ohooo". That's not worth a lot to me.
I can't help except to say anything that's "not so expensive" is probably not that good either.