I have a Tektronix TDS 1001, I found the same one used before for around 300 on the net. Ive had no problems with mine and i've had it for about 3 years ( it was bought used ). It is 1G sample and 40 Mhz bandwidth, both of which are higher then on the scope you are referring to... But it has no USB and it is a monochrome screen...
I guess if the manufacture you are buying from is offering a warranty and calibration, it might be fine.
But the scope will become your "eyes" so if its not doing something right, you will think its your circuit and go crazy trying to figure it out...
If you do get it post a review here and let us know..