Testosterone enanthate is used in many non-U.S. countries, whereas the cypionate ester is used almost exclusively here in America. These esters are quite similar, however, both providing about 70% testosterone by weight.  (The ester weighs 30% or so.)
So how much do you want to take? Well, first of all, the great majority of guys will do much better with weekly enanthate shots simply because weekly injections minimizes the fluctuation in testosterone and estradiol levels. So everything I say below assumes that you are going to get your shot weekly and not every two or three weeks.
Let me cover a few important assumptions first that you should go over with your doctor:
1. Physiological Levels. I think it is wise to not exceed “physiological levels” of testosterone, i.e. to not go over about 1200 ng/dl – the maximum that you would see in a healhty, young male during his peak years.
2. Estradiol Monitoring and Management. If you go to a peak of 1200 ng/dl, you will probably need some sort of aromatase inhibitor to keep your estradiol from going to high. At a minimum, you will need to be monitored to make sure that this is the case. In the U.S., low dose Arimidex (anastrazole) is commonly used for this purpose.
Based on these two assumptions, here are the typical weekly dosages that I have seen on the Peak Testosterone Forum and elsewhere:
“Hey guys a question about clomid, so my Doc has put me on 100mg of enanthate each week. When I asked him about clomid he looked looked at me like what is that! When I told him about it his response was that no one on TRT needs that.. yes I’m looking for an Endo. So my question is is it bad for me to just take like .25mg once in a while for a few day to make sure my E doesn’t get out of hand. When I asked to make sure we test me E level he just said they don’t test that and not to worry, so I will get my own blood tested independently I think.. Any input would be awesome .” 
“To determine the relative efficacy of several dosage regimens of testosterone enanthate in the treatment of male hypogonadism, we treated men who had primary hypogonadism with the following dosage regimens: 100 mg once a week, 200 mg every 2 weeks, 300 mg every 3 weeks, and 400 mg every 4 weeks, each for 12 16 weeks. Twenty-three men completed 37 dosage regimens.” 
And this makes sense: 100 mg of testosterone cypionate weekly is a very common HRT regimen and, again, enanthate is roughly equivalent to cypionate. Typically, when you see physicians wanting to give you 200+ mg of enanthate, it means they want to put you on an every-two-week or every-three-week schedule, which is not ideal in my opinion. Yes, it is a little more convenient, because you do not have to worry about as many injections. But this advantage is quickly negated by problematic fluctations in testosterone and estradiol. For more information, you can read my page on Testosterone Cypionate.
CAUTION: Always work with a knowledgeable doctor when it comes to testosterone therapy. Regular monitoring of T, PSA, hematocrit/hemoglobin, blood pressure and estradiol should all be done at a minimum on a regular basis. In addition, good injection technique and safety is critical.
3) http://www.guideline.gov/content?id=16326#top , “Testosterone therapy in adult men with androgen deficiency syndromes: an Endocrine Society clinical practice guideline.”
4) J of Endocrinology and Metabolish, 51(6), “Treatment of Male Hypogonadism with Testosterone Enanthate”