SSD Vs 7200 rpm + Thunderbolt?

[-pete-]

I'm looking to buy a 2011 iMac, I have a fair bit of cash to spend and I want this thing to last FOREVER (well at least 6 years) but the thought of blowing nearly £400 more on a drive 2/3rds the capacity of the original one (and thats without mentioning the stupid 4 to 6 week wait) is just too much.

Would be a viable alternative be to buy a SSD Thunderbolt drive when they start appearing? Since the transfer rate is somewhere in the region of 10Gbps wouldn't the slowest component would be the SSD (and therefore perform no worse than an internal drive)? Does anyone have information if these drives would be bootable?

Additionally, can Apple (or a third party) replace the drive later? And if so how much would they charge?

 

[negatv1]

Using an SSD drive in an external Thunderbolt enclosure (whenever those arrive) should be very fast, as fast as the drive can operate I'd imagine.

I'd hope that Thunderbolt devices could be used to boot, but haven't heard for certain.