Thanks for ur replies guys I will look into these tires.

 

Actually, the main reason I use 17"s is because it makes my gearing it a bit taller.

205-50/15 diamter = 23.1"
225-50/15 = 23.9"
225-45/15 = 23"

I use 215-40/17 which are 24". Yeah it's a small difference, but it helps. Not to mention, i'm not running boat anchor 17" wheels either..16lbs/rim isn't anything bad at all. Sure I could get some 15"s with 225-50/15 tires.. but all that sidewall would make it look like im rolling on airbags
I'll probably switch to a 225-40/17 when the time comes.

And I like a little 'bling' for my car since it's a daily... 15"s kinda look lost in the NB wheel wells (most styles...not all). Now , on a NA.. 15"s work great, 16"s do too depending on the style.... 17"s are a no no on NAs.

 

Your wheels look right on your miata. Don't change them. Just make more HP to make up for the added weight right?

17's and up on a miata look like 24's do on a cutlass and raise it too high off the ground if you don't go with a 35-45 series sidewall.