Thyrogen is just as effective as going Hypo for RAI and scans. It was approved for this purpose by the FDA. My Endocrinologist is a very mainstream Endo in a Harvard Medical School teaching hospital and I was administered Thyrogen for my RAI and will have it again for my upcoming scan in January. Now, if only they could come up with something other than that stupid diet we'd be all set :)
Most doctors will not do the thyrogen injections for the first dose of RAI. They want to make sure that your thyroid tissue/cancer will absorb as much of the radiation as possible. Liz is right - go hypo, do the diet, and get the scan. After that (for the yearly scans), Thyrogen is okay.
Go hypo, do the low iodine diet, and get a scan. Not pleasant, but effective. But, I'm not a doctor and I don't know the statistics on the thyrogen injections. All I can say is that my doctor would not let me do the injections the first time.