I have an early 90's P229 in .40 S&W that I've been shooting more. However, I hate the black plastic grips that came with it. What I despise the most is the bulge/bump on the top part of the left panel near the decocker & slide release. I've been looking at the Hogue G10 Piranha because they look like they have a flat surface instead of the bulge. Has anyone put a set on theirs and can tell me if they do have a flatter surface than the original grips?

Yes, the lump is definitely less prominent.

I have a 1993 228 that I just installed the Hogue G10 piranha grips on yesterday. Yes, the bulge on the Hogue grip is less than the oem grip. I too hated that bulge on the oem grip.

What they said ^^^

I’m probably in the minority, but that lump on the factory polymer grips actually helps me keep my thumb from riding the slide stop lever. I can also confirm though that the G10 grips from Hogue are much flatter in that area.

I'm just the opposite. The hump always made me want to ride the slide stop like it was the thumb safety on a 1911. Drove me crazy the whole time we issued 229s as duty weapons. I replaced the grips on all my personal Sigs with the Hogue G10s and greatly preferred them.

It's very much a matter of individual taste though.

Thanks everyone for your input. I'm getting me a set of Hogue G10 Piranha grips