I don't really think one is better than the other. I like straight enanthate personally. But so what, I don't think I would notice any real difference on sus, ara or enanthate at similar dosages.
As for which one gives gains you can retain better, none. If most of your gains are water retention, nothing will help you keep your gains (except maybe a high salt diet, lol). Keeping gains is, in my opinion, comprised of two factors:
1) Did you really make gains on your cycle, or did you just balloon up?
&
2) Your post cycle recovery.
Get those right, and you will retain most of your gains. If you forego the clomid, don't come crying to me that gear is horseshit. Also, if you do some a-bombs, and one piss after your cycle, you have already lost 15 pounds, don't come crying to me, either.
This is only one of the many reasons I like gear that does not promote water retention. Also, most people get better overall results when they add a highly anabolic steroid to the mix along with an androgenic (test) one.
This is why you see many people recommend test/deca or test/eq, etc. Stacks are recommended because they are more effective than just one a.s.
hth
txlonghorn