Honestly, you can't go wrong with either. Both cointaker and comet are great products, just different. I really believe it is personal preference with either. Also think the ablaze are very nice....I love their blue ones...maybe he best representation of the blue color out there...when I need blue I go ablaze.
Personally, I like ablaze for backglass illumination. Not crazy bright and they seem to "spread" the light better. That said I use comet in my bonebusters and they look great too.
I prefer comet for under inserts, nice and bright and focus the light in a smaller area so colors don't bleed into other inserts. Again, I have almost all ablaze LEDs from pinball life in my rollergames and I absolutely love the lighting.
In closing, use any product to upgrade your lighting, you won't be disappointed. I'd buy a little from each, install them in different areas and see what your cup of tea is.