maby i should be getting a logic analyser as well
Not if you are working on power supplies.
In fact if they are linear all you need is a DVM unless you are really keen to look at the noise in which case you should look closely at the vertical specs of a scope.
A scope is handy with switchers though.
Teks are good, but I'd say the a cheap ones probably come out of the same factory as the Owons/Rigols etc. Maybe not but some do that.
30MHz and 250 MSPS, while the Tek is rated 25MHz but 500MSPS
I usually look for about 10:1 oversampling, the Tek's 20:1 is good and I'm more likely to believe their specs.