Studies have shown that creams are pretty terrible. Especially if you happen to have thyroid problems. They seem to work at first and then fade out for a lot of people. Shots just simply work and are cheaper.
There are pros and cons to the various types of testosterone you could take. I'm using Androgel.
From what I remember when researching my options in 2007 (things have possibly changed a lot since then):
Monthly shots -- the thing with shots is that your levels go up right after you get your shot and slowly taper off. It's possible that your moods are a little off at the beginning and then you mellow out again by the time you need your next shot. Your options are to have a doctor do it for you or self-administer. Having developed an aversion to needles after my first bout of cancer, I kinda ruled this out quickly, even though it probably is cheap and effective.
Pills - easy but apparently not very good for your liver long term
Gel/Cream -- you have to worry about keeping your hands clean and physical contact, but it maintains your levels consistently since you're putting it on daily. It's admittedly inconvenient but works for me.
Orals shouldn't be considered.
Please excuse my ignorance on this, I am in Canada, have been blessed with naturally high T levels, and have no experience with anti-aging clinics, but I'm fascinated by the subject.