about the kernel 2.6 and ipsec

[Antonio José Espinoza Palenque]

Some help please:

I want to use the new kernel 2.6 to create VPNs using the new ipsec 
native implementation. However, Fedora Core 2 is in testing phase, but, 
I would like to use the kernel 2.6 with a text only Fedora Core 1 
installation.

my questions are:

Is it posible to mix the kernel 2.6 and Fedora Core1? if not, what 
possible problems do I face?
Is the kernel 2.6 IPSEC implementation and the kernel itself mature 
enough for real world applications?
Should I use freeswan and the kernel 2.4 instead?

Thanks a lot,
Antonio