why would the 150 water cooling make me sad?
$70 gets you a high-end HSF.
$150 gets you very low-end water cooling.
I think Aigo was inferring that you would be disappointed with the performance of the low-end w.c, resulting in you upgrading the w.c. components. At the end of the day you get what you pay for; spend $150 and it will be a bit better than air cooling. Spend $300 and pick the right (assuming you buy new) components and it will be quite a bit better than air cooling.
Edit: To put it in perspective; like a case, HSF and watercooling components do not change that much, i.e. the technology doesn't change at the same rate as say, a GPU or CPU. Hence it will last you years and can be re-used across builds, so at least it is a reasonably sound investment. All manufacturers do is tweak the basic principles:
1. The interface with the CPU IHS - the copper base of the HSF or the water block in the w.c;
2. The transfer medium - the heat pipes in the HSF or the pump, tubing and liquid in w.c; and
3. The heat sink - the copper / aluminium /etc. fins and fan(s) (if applicable) on the HSF or the rad and fan(s) in the w.c.