Just remember when you add something to the end of or even over a barrel of a firearm, the ATF can still get you for a suppressor. They did it with that GSG-5 22 that had the fake suppressor over the barrel, just like the look you are trying to accomplish. The manufacturer had to recall and replace the fake tubes even though no gases were exchanged. The ATF said the barrel cover quieted it down like 2 decibles and that was enough for them to take action. I know it sounds wonky , but with the Federal Government who knows. Over an airsoft rifle it's OK it's not a firearm.
I got one of the MFI shrouds. It's just for looks and it was inexpensive but I personally like the look of it more than the stock long barrel until I can get it SBRed and a can. It fits perfect about 1/4" Longer than the stock flash suppressor and is secured with just four set screws with a little nylon tip on them so they don't mar your barrel. Ultimately it's up to you to decide what's important to you and it you think there is any risk involved. I have acreage and seldom take it off my own property and if I feel like it's a risk I can just pop out the four set screws and slide it off.
don't see that causing much issue. As others have said, need to make sure the ATF doesn't up and decide it's a suppressor. I've stuck 15" cans on the end of my SBR and they still functioned fine. Not my thing, but different strokes for different folks