I would disagree strongly.
First off, buying over-the-top technology 'with an eye toward future upgrades' or 'future-proofing' is a terrible idea in computers, and ESPECIALLY in storage.
Ask the people who jumped at the first Terabyte hard drives how they feel 5 years later when they finally hit the capacity barrier. Good job with spending $100+ extra to buy 500 gigs of extra data that you didn't even use for like 2 years.
And now we come to you. Your example is even worse, as unless you get an ENTIRELY new system, you will NEVER be able to use the potential performance of the EVO. So basically, for the time between SSD purchase and complete system overhaul, you are more or less throwing away money. So much for 'future investment'.
But wait! There's more! Just like Hard drives, SSD performance/money and capacity/money is always increasing. So by the time that the hypothetical 'upgrade time' comes around, a much much better SSD will be available for much much less money.
And still more! Remember how I told you how the EVO was inherently bad? It uses a technology called TLC to lower cost that reduces overall drive endurance and long term reliability. The whole point being that power users who replace their SSDs often wouldn't care about it if it were for the performance/cost increases. However, in your case, you will not be able to take advantage of the performance increase due to SATAII. Thus, if you bought this drive, you are spending MORE money on a drive that is inherently WORSE in terms of reliability and endurance than both the Kingston and the Crucial.
To wrap things up, there is no reason under the sun that you should buy the EVO when there are all the alternatives available. Like the Crucial. Or the PNY XLR8 and Optima SSDs which are currently extremely cheap.