Based on the search results, it is not clear which specific model of Sandevistan David uses in Cyberpunk: Edgerunners. However, there are some suggestions and speculations about the type of Sandevistan he might be using. According to a post on the Cyberpunk Wiki, it is possible that David is using the Zetatech Sandevistan Mk.1, which has the highest time-slowing effect of all Sandevistan models. Another post on TheGamer suggests that Davids Sandevistan might be a military-grade Sandevistan neuralware, which grants him the ability to briefly experience a heightened reaction speed. A post on Reddit also speculates that Davids Sandevistan might be a rare and special one that cannot be bought off the shelf. However, it is important to note that these are just speculations and there is no official confirmation about the specific model of Sandevistan that David uses.