I have this model, at $279 its a great buy. I am tempted to get another!

Stock firmware acceleration and jerk settings are maxed you will want to change those. the test print gcode files print very slow, and look pretty nice, and desire for faster prototyping will take some tweaking and upgrading, but the foundation is all there to do that as you wish.

Only manufacturing issue I have noticed with mine is the stock Y carriage is way too thin, but getting an upgrade Y carriage (you will likely have to drill out the pillow bed hole pattern yourself) is a $25 addition that still brings it in under most other acrylic kits that come unassembled.

Check the y belt alignment. Mine came with the belt misaligned badly but it was fixable by reinstalling it with a longer m5 bolt reversed to go through the L plate on the pulley end and reversing the toothed gear on the stepper motor axle. Simple fixes to bring the belt inline with the Y axis and centered to the Y carriage.

Z Braces will be the first thing you want to print, then it is a good solid i3 variant.

I have zero regrets at $350, even not waiting a month if I had known about the sale.