"cheap" Switching power supplies?

[Art]

So... I've been looking on ebay for new power supplies and came across
these types:
http://www.ebay.com/itm/AC-110V-220V-TO-DC-12V-Regulated-Transformer-Power-Supply-For-LED-Strip-Light-/261470580279?var=&hash=item3ce0dc6e37:m:m_iaOWYh96gVhZmOESMtpKg

I know a few other places like jameco and digikey have these types of
power supplies, I was thinking about getting one or two of them for the
shack.... but I don't know how much hash they put out or how much the
fluctuate....

So, good deal or no?

[Robert Sears]

Buy one and I will take it to work and have the EMC guy scan it.

[Art]

I think one thing that I'm worried about is when the power supply comes
under a 90% load that there would be voltage spikes.

[Robert Sears]

A (well designed) switcher will have less voltage spikes and fluctuation
at a high load.

It's low loads that cause problems, because it's harder to control the
ringing at light loads.

[Art]

so would putting a large cap across the output be a good idea?

[Robert Sears]

That could help improve the transient response that switchers sometimes
lack.