A couple of years ago, I changed out all my rotors to stock, 9.5lb Solestice,
rear rotors. Yes, I was using these on the front, also, with modified brake pads.
I ran these for at least a year, with very good results.

But, last year, after searching to see if there was a better setup, that was still
as light, & easier to maintain, I have put together a better combination.

1st off, I am now a firm believer! in the Centric brand of brake rotors, &
only use this brand on all of my vehicles.

On the rear, I am now using Centric part# 120.40040 weight 7.5lbs
This is a stock, 2012 Civic SI rear rotor.

On the front, I am now using Centric part# 120.40021 weight 11.5lbs
This is a stock 1996 Civic front rotor.

With both of these rotors, you can use the stock HHR SS pads.
Both have 64.1mm hub size, & need to be increased to our 65.1mm size.
Easily increased with a Dremel tool.

Both need lug-holes drilled for our 5x110 size.
In my case, I'm still using my 4x100 hubs, during the 'racing' season,
& only need to re-drill the rear SI rotors, as they are 5x114
But, I do have another set of these rotors, that I have re-drilled for 5x110,
that I use from December thru April...
This can be easily done, with a hand drill.

The front rotors need a 3mm spacer, between the hub, & rotor.
Easily gotten on E-Bay.

So, I 'm still saving 100lbs with my rotor/wheel/tire combination,
over the stock HHR SS rotor/wheel/tire combination.
Stock HHR SS wheel/tire = 50lb
My 15"x7" Enkei wheel/street tire = just under 30lb
My 15"x7" Enkei wheel/slick = 20lb

 

Excellent Dave! I will use this info when converting my brembos so I can run 15" slicks.
Question, how can you be sure the rotors will be "centered" if using non-precise tools such as hand drills and dremmels to modify bolt pattern on the rotors?

 

Only need to increase the center bore by 1mm, total diameter, which is .5mm all around the circle, which is really , nothing...
By using a dremmel tool, it is very easy to 'sneak-up', 1mm by test fitting, with no issues at all.
With the rotors, as with all rotors, you have a 'loose' fitting, which means that 'close' is good enough, no need to be perfect with them...
it's the hub center-bore of 65.1mm, that needs to be 'spot' on.