They are all really beautiful locales. I personally LOVE reds/yellows/oranges and the darker/black bars that sambavas can have. Plus, some lines even show a bit of blue in the bars now (particularly the kammers lines.) AND sambavas are known for being a bigger locale so you could end up with a very impressive sized male (or female!) However, if you want one that might be more of a rainbow I would go with an ambilobe. There are tons of lines that have all sorts of color schemes. To me, it seems ambanjas tend to have more pastel/lighter colors, but some of them just explode with all colors of the rainbow.
Its a tough choice, and part of it will be what you like the best, which lines are available, how much you can/will spend, and how long you are willing to wait to get the "perfect" one. If you see/feel like you like a particular line/animal (or the parents if they are still babies) then go for it! You wont regret your decision.
