I have 31x10.50's on my 99 Blazer and I'm barely off by 1 mph. It doesn't really affect it. It is something to keep in mind though....I had a 97 Wrangler with 33's and it was way off.

 

I'm not worried about speedometer accuracy anymore, I've got me a Hypertech programmer to play with, lol

 

Theyre ok I guess but I would definately go with the OE rims or a good set of aftermarkets, but your blazer shows style and rebellion against the ordinary. Its what you like that matters!

 

As it turns out, these rims don't fit the truck anyway... The rears are fine, but the fronts don't clear the brake caliper.. You can only get like 3 - 4 threads of the lug nuts on, lol.

Now, I just gotta wait for my tires to get installed...

edit: my bad, the jack was too close to the wheel and it wouldn't go on all the way, lol