Ryobi BT3100 OEM blade worth sharpening?
 

It would cost me about $15, not so bad. But I wonder if you guys think
it's better to save the money and go by something like Forrest WWII or
not.

Thanks!

I have a bt3000 and a forrest ww2 blade, and I have not been able to
detect a difference in the cuts, either speed or smoothness, between
them. I have had the ryobi blade sharpened, and one tooth repaired, all
that was around $15 from a professional tool blade sharpener here in
Burbank.
The forrest has not been back to the company for sharpening and is
finally due. If anything, I think the forrest must have better carbide,
as it seems to stay sharp longer.
BTW, I also finally got a freud thin kerf rip blade, and it was really
worth it for my saw. Rips with about half the effort of a combo blade,
and just as smooth.
With the fence perfectly square to the blade and proper technique, I
get glueline smooth rips from any of the above blades.
Hope this helps,
Gary