Its around 40ms latency which is perfectly fine for freestyle/cruising, but racing where reaction time is key it can be an issue.
The tyro79 is too compact for a split camera as it requires an additional PCB (for recording and sdcard)
If your happy to build your own there are plenty of options available, alternatively quite a few manufacturers are releasing bind and fly 3" HD quads, so all you would need is a compatible transmitter and some FPV goggles. The Diatone R349 HD is around £150 and pretty good value when you consider the Caddx Turtle V2 is £50 alone.
When it comes to those, your options are either keep it sweet and simple with something like the flysky fs-i6 which is around £50 quid, fine for a beginner but you’ll soon want to replace it, or you can spend around £130 and get the FrSky Taranis QX7 which will last you for as long as your in the hobby, there are higher options but your talking £200+ then.
As for FPV goggles, by all means FatShark are on the high end of the market and the prices reflect that, I would suggest getting something cheaper to start with and upgrade as and when you feel the need.
Some possible starter goggles I would suggest are the Eachine EV800 (£40) the Eachine EV100 (£80), the Aomway Commander V1 or Skyzone Sky02S (~£200) and then of course you get the FatShark models like the Dominator HD3 (~£300) or the Dominator HDO (~£400).
Bare in mind for both of the FatShark goggles you will also need to buy a receiver module which is an additional cost of approx £60-£100.