I use the ones that work - irrespective of the vendor.

I have yet to find a good warm LED. They either aren't very warm or they are very green. This is part of the reason I started adding more color t the SM. Its also a reason why some colors look odd when using LEDs. Not that a cool white LEd isn't a good replacement in some cases. I just wouldn't change out all warm white incandescent with cool white LED.

As Action76 mentioned, my last bit of tinkering has been with filling out the yellow - which, along with orange, simply doesn't broadcast as well as others. In the case of SM, the best broadcasting colors are on either side of the yellow which only helps wash out the yellow. I think I've settled on the 3-LED fro lane dividers on SM and cointaker ultra fro the GI under the ramp. I have some pics in the other thread - http://pinside.com/pinball/forum/topic/cointaker-superbrights-vs-pinball-lifes-triple-led-lights

I find the retros work for GI lighting in most cased. I haven't seen the strobe effect others mention with them. For 89 flashers I used PBL 9-LED.

Any control lighting will need non-ghosting. I bought ablaze from PBL as cointaker doesn't have non-ghosting (but mentioned they were going to intro....but haven't seen them yet). I do tend to see a high freq strobe with the pbl non-ghosting when they are in a stead on state. I haven't found any warm non-ghosting yet. If you replace with insert lights with white, you will find some inserts look off because of the cool color (yellow looks green, blues wash out). Using color LED for inserts seemed to generally give you truer colors....but will change the hue some

I didn't want to add much brightness - more replace the incandescent and add color. If you are looking to brighten the whole machine, then you will likely need to step up the brightness throughout to avoid dark areas.