Thats crap, "I'm only good at field stuff, thats what really counts." A good soldier is good at EVERYTHING. When it comes to the field, unblouse them boots, wear the kit that works for you. So long as it is issued, or atleast you can still be identified by fellow soldiers. I'm talking load bearing kit mostly. When it comes to garrison you should look sharp as a needle. I hate soldiers who don't seem to care about shining there boots or looking sharp on parade/garrison.
ACU not also is a shiit camouflage, its shit quality, they fall apart easily, and the velcro needs to be replaced all the time. It also stains, regardless of how you wash it. That won't look good for garrison now will it.