Yes, you should use some tolerance because floating point operations are not guaranteed to yield the exact same results on different CPUs. There can be e.g. roundoff errors.
However, the SSE/SSE2 standards do provide reproducible floating point math, so you may consider using the compile flag /ARCH:SSE2 as an alternative. That said, it is difficult to ensure that no x87 math is used anywhere in the app, so be careful!