shurflo`
I've been running shurflos for 8 years, I have most of my taps on steep hillsides with 3/16 and 3/4 mainline. I have a few trees scattered here and there with several lateralsand 1/2" threaded manifolds. I use 3/16 even on flat ground because I'm in southernmost OH, at the end of the season I want the sap out of the tubing and into my dairy tanks as quickly as possible and the reduced volume of the 3/16 works better for this. I'm also pulling some laterals uphill with the 3/16 and although 5/16 will pull uphill as well, there's a lot more sap stayin in the line than with 3/16. Line friction is higher on 3/16 than 5/16 if you are doin natural gravity and have flat places in the run, but the shurflos easily overcome this. I have a couple of laterals over 1000'. I started out with a single hand 5/16 tool,bought it before I found out the advantage of 3/16 on slope, I cut a piece of 5/16 1 1/2" and slit it end to end, slip it over the 3/16 and it works very well, I used that for 500 taps for 4 years before I got a deal on some used 3/16 tubing tools.
'12 15 jugs - Steam pans
'17 125 3/16 - 18" x 72" drop flue on homemade arch
'18 240 3/16 - Deer Run 125
'19 450 3/16 - Converted RO to electric/added a membrane
'20 600 3/16 - Maple Pro 2x6 Raised Flue, added AOF/AUF
'21 570 3/16 - Built steam hood, Smoky Lake filter press
'22 800 3/16 - Upgraded RO to 4 4x40
'23 500 3/16 - Re-plumbed RO, new "Guzzler"
'24 500 3/16 - Steam Away, DIY 8x40 RO