There are many types of lights all over, and it sometimes confuses.
If you want to buy something good, which will satisfy your needs for a long period of time, you should specify some simple questions that might help you to focus:
1. What's my maximum budget ?
2. Is it a main light or a backup light ?
3. Should it be Halogen (usually Yellow) or Led (usually White) ?
4. Should it be sheaf or bubbly ?
5. What's the maximum depth ?
6. Battery type (Size, Charge).
Maybe there are more questions, but that's the main idea.
Example: An underwater photographer sometimes prefers a small secondary sheaf light to search for objects, and a main chargeable Led bubbly light to photo the object.
But... it doesn't have to be like that- Another photographer may want a main nonchargeable Halogen bubbly light, because it goes better with his camera.
So, as you see- you and only you can identify the answers to yourself.
The next step will be much easier- Simply try to find the lights which answer the questions, and than pick the best which suits your targets.
Have a pleasant purchase.