Bold or Curve 8900 on O2 Germany?

I'm really confused. I was really happy with my Curve 8900 for the last night until I left my Wifi the first time and only got GPRS connection. The problem with o2-Germany is that in cities there is only HSDPA and GPRS but no EDGE. I tried Google Maps and some websites. It was really slow. So I called the service and they said I can get the Bold instead. So what should I do now.

Here are my questions:
-How is battery live of Bold(UMTS) compared to Curve 8900(GPRS)?
-Is the Bold much bigger?
-They both have 4.6 but is there aqny difference in the software?
-They have different processors, so what about speed difference?

I really don't know what to do! :confused:

And there is one more problem: since you can only call or have GPRS connection it sometimes seems as if calls don't come through when the Curve is receiving data (one point against the Curve)