Looking to get: XXR 530 rim

2 set ups:
Square set up:
19x8.75 +15 offset

Staggered:
19x8.75 +35 Front
19x10.75 +35 Rear

I can't see this rim in real life so I don't really have an idea of the concavity but I was wondering if anyone had an idea? I would prefer the square set up to rotate tires.

Square
https://www.ebay.com/itm/XXR-530-19X...53.m1438.l2649

Staggered
https://www.ebay.com/itm/19x8-75-19x...53.m1438.l2649

 

Just found the staggered set up with +15 offset as well.. is this too aggressive for the IS 250?

https://www.ebay.com/itm/19x8-75-19x...53.m1438.l2649

 

For the square setup the offset is way too low...you would need something around +32 to clear the front fenders.
For the staggered setup the front is fine, but the rear is gonna hit the fender for sure. You would need something around +45 for the rear.

You can do a square setup with the 19x8.75 +35 without issues.

 

Was thinking of going with 19 x 9.5 +15 offset wheel.. will have to roll fenders and "add negative camber". How do you think this would affect tire wear? Heard I might only need to tilt it in 2-3 degrees

 

The rear fenders are actually factory rolled already...the front you can roll a tiny bit. You would have to pull the fenders and body work them to fit what you are suggesting.
Just to give you a visual of what 19x9.5 +15 would look like on an IS, if you managed to make them fit, see the LS photo below.
The good news is the outside of the tire will never wear, likely it will never touch the ground. The inside would probably last 5k miles.
Jokes aside...you could fit a square 19x9 +30. Nothing wider will fit the front.