Well I've had two surgeries on my left knee including an ACL reconstruction a year and a half ago so that knee will never quite be the same and every little helps. I have a hinged Shock Doctor knee brace but it's not very practical, comfortable and can't even get a full bend for a squat with the hinges anyway. Also feel a little silly wearing it due to the size.
Actually just nabbed a XXL Rehband 5mm for £7ish on Amazon warehouse after the 20% off offer that's on there. Another XXL left for a tenner so be around £8 with the discount if anyone is that size.
Just bear in mind that knee braces do nothing to support a healthy knee; practically, you are keeping it warm and tubi-grip does the same job for much cheaper.