I also feel that no one method is always the most appropriate.
I believe that Reiki is real for me, and for many people I know. For me it has strengthened my connection and awareness of the energy that flows through all things.
I also believe that from a rational perspective, to only utilize one method of healing, is potentially limiting the chances for healing.
Personally I use Reiki in combination with other healing methods, dependent on the situation, while i myself am not a big fan of orthodox medicine, it still has it's place, as do many many healing methods.

With Reiki I have found that a large part of how well the healing works depends on the person who is receiving the healing, and agree with Gem and doogatyee's comments that the "healing" may not necessarily manifest in the way we would think.

I am hypothyroid. If I don't take my medication, I start losing my metabolism, and eventually I lose my hair, scratch my skin raw, and experience extreme pain in my digestive tract as things start to shut down. I also teach Reiki and use it on those around me. I believe that it is helpful in conjunction with other things. I have had much success in combining Reiki, Reflexology, and Aromatherapy in my practice at work, and at home, but I wouldn't use anything exclusively and abandon my medication. That would be silly and irresponsible of me. I believe that the use of alternative therapies have allowed me to stay at a very low dose for the last five years and I will continue to use them in that regard.

Besides, "healing" doesn't necessarily mean no more sniffles, or no more infection. If we set ourselves up for how the healing must manifest then in many cases we will be disappointed. When my son broke his arm skateboarding, Reiki didn't make the pain go away, he said it actually hurt more when I did Reiki. One of the things that his dad and I both noticed, though, is that after each Reiki session, he wasn't as angry at himself for messing up and falling down. According to the doctors, even as he was being given a sedative to put him to sleep for surgery, he was still carrying on about how stupid he was for falling down, to anyone who would listen.

~Solwynn

If we set ourselves up for how the healing must manifest then in many cases we will be disappointed

I absolutely agree here.  It is not my place to decide what a person does with the healing energy.  That belongs to the recipient.  Their mind/body/emotional being knows best the use of the energy and I do believe the use will be their highest good, whatever that might be, whatever the result.