While it is possible to use a splitboard without a dedicated splitboard binding (by using Voile Slider plates attached to bottom of a conventional snowboard binding) at this point it is not recommended. This set up will work ok for a few short trips but the even the heaviest splitboard binding is significantly lighter and worth the investment. Splitboard bindings are the biggest innovation to splitboarding since the splitboard and noticeably improve the overall experience.
Currently, splitboard bindings can be lumped into two broad categories. Puck based bindings offered by Spark R&D and Voile and then the Karakorum system. All these represent an improvement on bolting on slider plates but there are real differences between the two categories. To briefly summarize: the puck based models are cheaper and simpler, while the Karakorum offers the allure of increased performance with increased cost and complexity.
Remember that splitboard bindings are tools for climbing (and descending) mountains. Weight matters and saving energy on the climb will leave you with more energy with which to enjoy the descent. Lower weight can often result in a simple streamlined product without a ton of features.
If price and weight are important deciding factors for you, the Spark R&D Arc is the lightest binding we tested. The Voile Lightrail was the cheapest but we recommend the Spark R&D Blaze for the budget conscious as the price is only nominally higher than the Lightrail but weight and performance are noticeably better.