What are some alternatives?
When comparing GRUB and Grub2Win, you can also consider the following products
EasyBCD - EasyBCD is NeoSmart Technologies multiple award-winning answer to tweaking Windows bootloader.
PLoP Boot Manager - The PLoP Boot Manager is a small program to boot different operating systems.
Visual BCD Editor - Visual BCD Editor - advanced GUI version of bcdedit utility. for Windows 7/8/10 and Vista
EasyUEFI - Manage EFI/UEFI Boot Options & Manage EFI System Partitions & Fix EFI/UEFI Boot Issues
Grub Customizer - Grub Customizer is a graphical interface to configure the GRUB2/BURG settings and menuentries.
rEFIt - rEFIt is a boot menu and maintenance toolkit for EFI-based machines like the Intel Macs.