There is a substantial amount here under the search feature > try Trout Spey as a search.
If your going to spend that kind of cash, you may want to try it first.
They are ideal for swinging wet's, streamer's,tubes on larger riivers.
Some bobber fish them along with swing. I just swing so I am not sure what the ideal, latest,greatest lines are for switch rod nymphing?
For swinging, You will find the consensus is a rod, spey casting about 250-350 grains depending along with shorter switch rods in general (10'-11').
I have owned,fished a half dozen differant trout switches to mini Trout spey's, and a glass switch.
Personally, I like short 10'-10 1/2' (light,sporting and easier to C & R Trout mid river with ) and a Scandi multi tip shooting head of about 275'-300'. I also like a bit deeper flex rod. Some like a bit longer rod, to mini speys, some skagit heads.....a few fish equalvenets of 4x short belly spey lines with trout soft hackles,spiders,etc................you will have to find out what you like, on your own................not everyone likes the same.
There are many available now both short - longer Trout two handers along with more lines
FWIW - Currently I use a Thomas & Thomas 10' 5wt, two hander / "switch" Rio Scandi Short VT shooting head, Airflo Braid shooting line. For value rods made off shore I would look at Beulah Classics, Echo Switches,Redington,etc. etc They work fine too.
Myself and many others also use them for river Smallmouth Bass.