I have a euro 230E. The engine mounts went in 3 years. The passenger side one was the one that went bad becuase of the engine twist during acceleration. Too much stop and go traffic and red light races I gues . The original lasted to 130k km. Bizzarre but, judging by mercedes recent quality, not surprising the new ones went so soon.
If you want to see if yours is bad. Pop the hood (bonnet) and hold the engine in gear with the brake and give it some gas. If the engine twist significantly you've found one issue at least.
The hard start could be your battery and/or a bad cold start valve. Get yourself a multimeter and see if your battery is 13v or above while idling or 12v or more after sitting for awhile. I think someone posted how to test the coldstart valve somewhere so do a search.
Hope this helps...