Hi there! I thought I would reply since I just went through something similar to this. I'll give you background first. 58yo when diagnosed in 2004. Had 2 rounds of chemo and 35 rads.
For reconstruction, I did have my doubting moments, but overall everything was good. I started recon in Jan 2009 with chest expanders. (I was lucky to have reconstruction at all -- thin so I had to have chest expansion on radiation damaged tissue). The worst of these processes for me was the initial chest expander. I was really down because of the tenderness of the skin. Skin that was being expanded was very sensitive because of the radiation.
In April, I had the permanent silicone implant with a Lat Dorsa flap -- skin moved from my back to the chest so they could do away with the bad radiated skin. No problems, but a little soreness.
In May I began rehab so I could lift my arm -- remember I had radiation and also 5 positive lymph nodes.
In June, I had maxtopexy to lift other breast and some revision of reconstructed breast. Lifted breast was sore for about 3 months, but very tolerable. There was almost no pain in the reconstructed breast.
Your course of treatment will probably be different. Many people have only a two step process, not three as I did. As for pain, it is different for everyone, but for me, reconstruction pain was small compared to the pain I had right after mastectomy.
Hope this helps with your decision.