Basically I had to use a breaker last weekend, it was clear I did not need the “heavy duty” as I did not have 6” of solid concrete, but the descriptions of the other options confused me.
The SDS chuck system was the original developed by Bosch.
SDS Plus is an improvement on the original SDS system, but remains compatible with SDS bits, and is now the most commonly seen on the market.
SDS Max is designed for the heaviest masonry work, and is incompatible with SDS/SDS+ bits.
It sounds like for your application, SDS Plus would be the way to go, given that they are generally less expensive, and you don't have really tough masonry work to do.
Really I would suggest using SDS Max on the larger projects where you are doing some Demo. SDS Plus is however a lot lighter and easier to move around with, as long as you dont need to go super heavy duty.
You can get adaptors to convert between systems like SDS Max, Plus and Spline.
SDS Max Shank Carbide Bit:
You can find some good photos of the various bit types at www.BuildersDepot.com. Link: https://www.buildersdepot.com/carbide-drill-bits.html
In short, sds + is for light duty applications (drilling for ledger boards and light demo), sds max is for people who work with and demolish concrete professionally. I build decks and fences. For me sds + does everything I could ask. Good for breaking up old peirs, drilling multiple large (up to 1") holes in brick or concrete.
If your doing domestic builds, small-medium shops, garden patios, sheds etc SDS+ is great. If your working on a tower-block, building a mall, shop from scratch, SDS Max. It's not just about the bit but the tool your connecting it to. An 18V set of tools are great with SDS+ for example. The battery pack you choose, if using cordless, will also have a big bearing on the quality of the end job. If buying or using corded make sure the voltage is compatible if working of a generator on site.