Obviously they’re recommended to run 44mm offset forks but anyone running 51mm and if what’s your thoughts..?
I've not got your exact situation but I did agonise over putting a 44 offset on a bike meant for 51. Also, with a 650b bike that should have been 46, I fitted a 42 without knowing and then agonised over upgrading to 37.
Unless you're hyper sensitive and do back to back testing, I don't think you'll notice. It's amazing just how quickly we adapt. I certainly wouldn't scrap and replace a good fork just for the sake of offset. The money you don't waste would get some new tyres or a shock tune. No there's a couple of things I reckon you'd be more likely to notice.
It's literally one of the factors to how the bike will steer and handle, you can counter that 7mm of offset by handlebar length, stem length, tyre pressure, etc, etc. I wouldn't get too hung up about it, it's always nice to have something that handles well at lower speeds, but again, you can do many things to counter this any way.
I wondered this but then realised you can get a rock shox CSU for as little as £170 (b1 pike) and sell on your old one to someone with a creak.