Has anyone used these before http://www.helmetworld.co.uk/airsoft-tomtac-m4-scar-hi-cap-magazine-mag-300rds-winding-wheel-aeg-tan-de-metal-40306-p.asp are they any good as they are only £7.70, I was going to use them in my CM16 raider L thanks in advance to anyone who can help me out.