Seems okay for 40 bucks up until I saw that it's 30 dollars for shipping, find a different supplier, there are units like this available in the states for less shipping.
For hobby work, I'd suggest going with an old (but still functional) analog scope, I picked one up for 30 dollars (including shipping) for a 500khz tube scope that was quiet nice for audio and basic electrical testing. Bargain hunt for those older analog scopes they'll have better overall features and capabilities and be a little more useful.