I bought this saw as a general purpose tool, mainly to help ease the work of sawing up logs and branches for firewood. It's been excellent at this, reducing a large pile of long timber to neat short lengths far more quickly than I could have done by hand.
The build quality is good (standard Bosch quality - with a nice robust feeling moulded body).
I found the blade change mechanism easy to use and quick (simply push a slider -it does need a firm push, but I'm glad it does as you want the blade secure.
I have not yet needed to replace the blades - treated well they seem to have good durability (there were 2 included, one for wood the other for metal) so can't comment on the replacement cost - I'm sure I will search on the web to see what deals there are to be had as and when I need to.
In use the unit does vibrate so you may want to take breaks after several minutes of continuous use - but it's not at an unacceptable level. I also liked that the saw is reasonably light (lighter than a more standard reciprocating saw) so more manageable in quick day to day use.
Overall a good purchase that I have also used for general Internal DIY, and would buy again.