Just to add to previous posts: having a bypass doesn't necessarily mean you WILL dump, not everyone does. I for example had a gastric bypass, and have never dumped - not even on very sugary fruit juices (lived on those for a while when I had trouble eating).
Most research points to the sleeve and the bypass being equally effective at two years out. Bypassers however tend to have most of their weight loss in year one, whereas the sleeve is more "slow and steady". Obviously this differs from person to person however, we have sleevers in here who dropped most if not all of their excess weight in year 1 as well. Which one to choose has more to do with what your eating habits look like, co-morbidities etc. A bypass has for example shown to have a positive effect on type 2 diabetes (beyond through just the weight loss itself - something to do with the bypassed intestine), which is why many people with diabetes opt for that.
In my case, the reason for choosing the bypass over a sleeve had to do with me already having bad acid reflux. A sleeve sometimes makes that worse, as the new, narrow stomach has an increased internal pressure. The bypass pouch does usually not have that same issue as you no longer have the pyloric valve. I never had much of a sweet tooth (I'm a salty/savoury carb type of person) so that really never factored into my decision. Which is a good thing, obviously, since I don't actually dump anyway.
I originally wanted a sleeve - the idea of rejigging the intestines creeped me out a bit and felt so drastic. A sleeve surgery is generally also shorter, so you are not under anaesthesia as long. But after a lot of research and discussions with my surgeon, I decided a bypass was more suitable for me.
Mazza is right in that you should discuss this with a professional - your provider should be able to advise you further as they presumably have your full medical history etc. Remember to be very honest with them about what your eating habits look like, so they can give you the best possible advice.