No idea. Claramont has been REALLY vague with her power levels. But she's the ONLY Earthling that survived the Chaos Wave in the House Of M without changing.
My gut says Rachel, but I think it depends on the situation. Rachel has such a great arsenal at her disposal, but IW is a bit more seasoned. Now if this were current power Rachel with the mind of Mother Askani, it would be no contest.
I still don't know whether Sue can shield herself against telepathy or not...if she can, she has a chance.
Emma is not as powerful a telepath as Rachel, but was able to beat her, because she was a BETTER telepath (just like Xavier and Dark Phoenix)... likewise Rachel might be the more powerful telekinetic, but i dare to say, that Sue is the BETTER "forcefield-telekinetic".
The odds remain in Rachel's favour though.
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THE CORPS IS FATHER
yea, I think Rachel like X-Man was has great potential and power but the experience and discipline of a toddler, Rachel is very creative w/ her teke but so is Sue w/ her fields, its really about Rachel's sheer limitless power against Sue w/ incredible power and experience, depending on the situation the odds might top toward sue or rachel but im like a 5.6/10 for sue and 5.4 for ray