At that cheap price, I'd be very suspicious of cheap lenses, cheap bulb mounts, and poor beam pattern.  Projector beams require that everything be of excellent quality and properly lined up... and at $20 a pop, I'd be dubious.  They'd be better than 7" sealed beams, but not nearly as good as these proper 7" H4s:  
http://www.danielsternlighting.com/products/products.html
or 
http://www.busdepot.com/0301600118

If you want better - far better - light out of your 7" rounds, you can't go wrong with Cibie or Bosch.... you might with a cheap 'projector' replacement.

James
Ottawa, ON
'91 Weekender (which won't take a 7" round without first installing an SA grill)

> Date: Tue, 13 Jan 2015 15:08:31 -0600
> From: ralphmeyermann@GMAIL.COM
> Subject: Re: H4 upgrade?
> To: vanagon@GERRY.VANAGON.COM
> 
> Check out this item I found on eBay:
> 
> End time: Jan 29, 2015 10:02:09 PM
> 
> Item: 7" Projector Clear Lens Headlights Round w/ H4 Light Bulbs
> <http://pages.ebay.com/link/?nav=item.view&id=301465416911&alt=web>
> 
> URL: http://pages.ebay.com/link/?nav=item.view&id=301465416911&alt=web
> 
> (Sent from eBay Mobile for Android)
> 
> Velma 82 1.9L AAZ TD Westy