I had a $350 Da Vinci on loan and then I gave it back and got the one from Fast Tech. In my opinion the $18 dollar one from Fast Tech is equal to the Da Vinci.
Both ovens only got a little dusty with dry herb. Not like a pipe that gets a tar build up. Clean with the included brush in 5 seconds. Putting an oil jar in the Da Vinci could get really messy and was a painful half hour to clean.
And like Niall and I said, vaping is a different experience so now you can try it for under 20 bucks.
For smoking smoking oil (as opposed to smoking edible oil) I will recommend the CCELL Palm.
https://www.ccell.com/Product/BATTERY/PALM
Probably available at a local shop. And the photo with the hand is either a bad photoshop or a really small hand because the unit is about 20% smaller looking in my hand.
The ccell palm is nice for oil. No preheat and no buttons. Just take a pull and it goes. Super stealthy, although I've never needed to be stealthy. But on the other hand, I might want to stealth vape at a concert. Drugs make music sound better ;)
I am really not sure but I think edible oil is cut with cooking oil so it splatters, pops and sizzles in vapes. But I know some one who says edible oil smokes great in the ccell palm.