Welcome to Treebuzz!
SRT is the future of tree climbing...IM[not]HO...hahaha!
First...only use gear that is designed to fit the rope that you are using. This is VERY important because the camming action of the device is dependent on where the cam is located on it's arc of travel to lock down properly. Oh, sure...people have been using Gri-Gris on half inch rope for a long time. But, is that proper? No...
Look at it this way...how much chatter is there on Treebuzz about people doing bad treework? Leaving stubs, ladders without personal support, no PPE. My point is an extension of this...use the right tool in the right way...or it's wrong.
OK..off the soapbox
When you get to your TIP-tie in point-and are goingto make the transfer put your lanyard onto a secure place. Then, take off your ascent gear. PUt on the descent gear and TEST the gear BEFORE you take off your lanyard! There have been accidents and deaths because the climber made the gear transition but didn't test the new attachment. When I transfer I'll snug up the new system, bounce on it with my lanyard still snug, then slack off the lanyard, bounce again and look carefully at how everything works. Sometimes I'll even do a third test before taking my lanyard off.
Any descending device is likely to have a sweet spot. Some are easier to hit than others. There are a wide range of variables too. Climber's body weight is one. The rope is a HUGE variable. Is the rope supple and squishy? Is it a hard lay like flexible cable? Is the sheath smooth or is it a twelve strand with lots of bumps and texture?
My personal favorite for this application is the Eddy. There are some shortcomings...the climber needs to be aware that the cam might not grab in certain configurations and allow a slip...not a fall though, so far. Having the ability to lower by either pushing or pulling the handle makes for some nice use. In either setup the cam will go over center and lock down. Hard to argue with that feature. Pull a handle on a Gri Gri too far and what happens...fall!
Plus the Eddy can be setup so that the rope comes out of the bottom in a more natural feeling setup.
The MOST important thing that climbers should do more of is to tie backup knots in their rope. I'd like to see this become more normal for all climbers. But...I'm not going to fight for that, just suggest.
Every few feet take up a bite of rope and tie a slip knot in your rope. If you ever slip on the rope you won't take a grounder.
ON ROPE should be mandatory reading for anyone who makes their living hanging on a rope. YOu should be able to find a used copy pretty cheap. I've seen them for sale for $10.
Take the time to read through this WHOLE site:
http://storrick.cnchost.com/VerticalDevicesPage/VerticalHome.shtml
There is soooo much information there!
There is plenty of discussion in the Treebuzz archives too. Look up the SRT or Eddy threads. Google will take you to other info from the vertical world too.
Ask lots of questions and stick with your thread. It's easy to find a thread derailed and your original question may not be answered.