The 295 isn't going to chirp. It's adjustable frequency though. If you want to study the bottom habitat, fixed freq non-chirp is very desirable. You can use a chirp compatible transducer for that.
With the 800 you could chirp one transducer, and have the other at a fixed freq.
The 800 seems decades newer tech...
The 295 has a landscape format which is good for split-screen use, where the tall format of the 800 is ideal for non-split screen use even if it can split screen.
If money isn't an issue, I'd probably get two 800's and add a 50/200 transducer to the mix and run two chirp and 50/200 at the same time.