There is not much benefit of using version 14.x over version 12.5.9 using the same Haswell CPU.
Most of the Haswell specific CPU features (examples: INVPCID, MOVBE instructions) are already exposed to the guest VM with version 12.x (possibly earlier with version 11.x).
Using the Spectre/Meltdown patches as an example:
For Meltdown, the INVPCID is already looked at by version 12.x and exposed to the VM. The INVPCID instruction requires minimum hardware compatibility version 11 to be exposed (which suggests Workstation version 11.x already did that, too). You can see lines like these in the vmware.log.
| vmx| I125: Capability Found: cpuid.INVPCID = 0x1
| vmx| I125: VM Features Required: cpuid.INVPCID - Bool:Min:1
For Spectre, assuming the CPU has the microcode updates, version 12.5.9 exposes the 3 Spectre microcode updates
| vmx| I125: Capability Found: cpuid.STIBP = 0x1
| vmx| I125: Capability Found: cpuid.IBPB = 0x1
| vmx| I125: Capability Found: cpuid.IBRS = 0x1
| vmx| I125: VM Features Required: cpuid.STIBP - Bool:Min:1
| vmx| I125: VM Features Required: cpuid.IBRS - Bool:Min:1
| vmx| I125: VM Features Required: cpuid.IBPB - Bool:Min:1
On a Windows 10 VM, with the proper CPU microcode and OS patch, you will get "all green" in the Get-SpeculationControlSettings Powershell with version Workstation Pro 12.5.9. Windows 10 requires the INVPCID instruction for the PCID mitigation to be TRUE.
On a Linux VM, you can see in the flags of /proc/cpuinfo: spec_ctrl, invpcid, invpcid_single
