PFS is about resistance to key-compromise, not about growing computational power.
If you're afraid of faster conventional computers, use sufficient key-sizes. e.g. a 4096 bit RSA key or a 256 to 512 bit ECC key. At least for the 512 bit ECC key case, we can safely say that conventional computers getting faster is no threat.
Unfortunately large RSA keys become pretty slow, so at high security levels ECC is preferable.
For SSL the easiest way to get ECC for confidentiality is using the forward secure ECDHE suites. But that those suites offer both PFS and higher security levels is merely coincidental, the security level in bits and PFS are not directly related.
=> Go with ECDHE suites where available. They offer both PFS and higher security levels with decent performance.
For long term security, I'd worry more about quantum computers, which kill both ECC and RSA using Shor's algorithm and about mathematical advances which might break either of them, or both.