Hello, all fine with Rigol or similar oscilloscopes, but there's a very important technical specification that often is not considered, which really DOES the difference between a cheap oscilloscope and a powerful one: waveforms per second. Suppose you are searching for a rare glitch, or that you are trying to trace an edge of a signal with infinite persistence. If the scope is a DSO, it just takes a sampling window, the memory is full and requires data processing and display, in the meantime the signal is not analyzed, and you can lose important events. A DPO can capture the signal continuously, or at least with very short death time, and the display is updated using a large number of triggered sampling windows. Of course this kind requires a far powerful acquisition circuit. I really like DPO scopes in place of DSO, for example used Tek TDS540C or D, they are quite cheap, no electrolytic caps, and can be optionally expended to increase acquisition memory depth. Display is small and grey, but you can use a VGA monitor. My two cents. Andrea