I'd been debating on trying it for the last few months, but finally decided to pull the trigger a few days ago...
What the heck was I waiting on??? I love it! The tabs are great and I love how you can do the "desktop rendering" and avoid mobile sites. One of my motorcycle forums automatically defaults to the mobile version and, though it offers the option of going to the desktop version, it actually doesn't work. But on Perfect Browser, I can force it to work and it's great.
Yeah, this is one of the features Perfect Browser has been advertising since almost the start (it's been one of its main selling points). It doesn't auto hide but you press a button and it will hide both (and the button remains opaque so you can press it again if you need them. As well as the back and forward buttons).
I'll be honest, it kinda sucked when I first got it cause it was glitchy. But it had such useful features I used it anyways.
Now it's not glitchy (They fixed it in 2.0 I think) and those features remain (and have gotten improved). I think it lives up to the name now. It has all the features Apple seemed to leave out of Safari (remembers your tabs, you can make both the bottom and top bar go away but it still has opaque back and forward buttons so the only time you need the bars to come back is if entering a new website address, has a search function, the tabs are on a collapsible bar that you can view all that are open at once, it has a speed scroll if you choose to use it, the address bar can be brought back with a button and it stays with you rather than scrolling up so if you need it you need to scroll to the top again, when it's loading a page it shows a page loading bar at the bottom with a big stop button in case you made a mistake... I hated how safari if you accidentally clicked something you had to try to scroll quickly to the top to get to the stop loading bar).