Take breaks to check on Glans condition, remove device & restore circulation periodically.
You need to build up how long you are wearing it (sessions), over a few months. What I am saying, is don't try to start wearing it 8 hrs non stop.
I've put 5500G springs in my extender to break a gain plateau; it's very hard to stay strapped in, prevent slippage and bruising; it can be done if you're very careful, inspect frequently and know what you're doing. You need to use a strong strap over the silicone strap to hold everything in place and you will need some padding or wrap that will hold up under all that tension.
A vacuum attachment is possible too, but the vacuum pressure will be extreme and blistering may occur.
I have tried both methods successfully (short term) to break plateaus in gains.
Depends on the effect your head piece has on your glans. If the strap does not cause the glans to get cold, it might be good to go for long stretches, but this need to be tried and checked before committing to a long period.
I have a vacuum based head piece and I find that after two hours my glans gets cold and occasionally causes bruising.