I like a tight setup. So a close foregrip is what works for me. But I also like a handguard feel too. So… The Mercker fits the bill for both.
I use the magwell and magazine as a foregrip as well as hold it traditional rifle style. But most of the time I tend to use the area just in front of the magazine and the upper part of the magwell (as opposed to gripping the MAGAZINE as if it was a foregrip).
ADDED: And no, the foregrip in my signature image is not in use. It was there for the "photo op" only.