Well I stuck it in and all I can say is - pay Apple to do it!
The 'OEM' screen isn't OEM, the colour palette is completely wrong, the digitizer is inconsistent and the home button doesn't work once fitted to the new screen - although I believe a lot of people have had this issue, which is reported to be a deliberate tactic from Apple to prevent people from repairing
their own property themselves - and lastly, the 'OEM' screen doesn't clip back into the casing properly, so sits proud on one edge.
Also worthy of note - On the iphone 7 onwards, the screen is bonded in with a butyl rubber strip, which you don't get with a new screen (obviously!), so it is no longer splash proof with a non apple screen.
Oh and those £2.49 tool kits are complete garbage, don't even go there. The star tool bit doesn't even fit the screws
Pay a bit extra and get the proper metal tools and metal pry tool from higher end repairers.
Oh and be careful removing the old screen if it's chipped on the edge. I got a nice shard of glass flick up into my eye
Once again, the old 'Buy cheap, buy twice' mantra has to be trotted out here. I've done quite a few iPhone 5 / 5S and one or two 6 screens, but the 7 onwards is a different bag, and a whole lot more fragile.