I wonder what is your provider of Magento Extensions? I am using Magento Extensions from MageHit and i am quite satisfied. They provide good products with acceptable prices. Besides, their service is quite good, enthusiastic supports from experienced experts in Magento and Ecommerce. What is you choice? this site : http://magehit.com. I am using Magento One Step Check out and Magento Reward Point Extension.
You can also try FmeExtensions, One of the leading Magento extensions provider with 120+ Magento extensions. The good thing about this company is they offer 45 days money back guarantee with free support and free upgrades for lifetime. You can checkout their new top quality Magento 2 Extensions here.