I have never had nor used a Bosch mixer, but I did have a Bosch dishwasher. As is typical with "high end" appliances, it worked like a charm - *while* it worked!
It lasted about a yr before we had to start replacing parts (which is VERY expensive) and finally after about a yr and a half, we ditched it for a much more reasonably priced Kenmore Elite - no problems yet!
I've found the Bosch to be great at creaming butter and sugar, but the design is very unusual (more like a food processor). I've found that it overprocesses dough if you use the times recommended by most recipes. If you're willing to adjust accordingly, I'm sure it would be fine.
Cook's Illustrated recently recommended the KitchenAid Pro 600 (which I've had for about a year and have enjoyed great sucess with). Their second-place model was the DeLonghi DSM5, which they liked almost as much. The Bosch came in close to the bottom of the 12 mixers they tested.
Good luck choosing!
I bought a Bosch for my sister a number of years ago because she wanted a decent mixer, but had very limited counter space. I think it was the 400W model, not the 700W. I think it was best suited to cakes and cookies, but she was also quite happy making small batches of bread with it and no defects. Personally I use a Kenwood, which is now the DeLonghi which I preferred to the Kitchen Aid (classic) but its given me so many years of service that I haven't compared it to current versions.