I decided to get a Vanguard Equalizer 2 bipod (13-27") which will end up on my 243 for hunting.
The price on eBay was $120 and the build quality is first rate. It is aluminium so it only weighs about 430g, the Harris is about 540g.
On the shortest length it is usable for shooting prone but you need to lift your head.
1 extension is good for sitting and 2 extensions for kneeling.
It doesn't have the usual springs on the legs like the Harris and Champion which looks better imho.
Unlike normal bipods the mount sits on a medium spring so it allows a really good range of movement without shifting the legs (they say pivot tilt of 0 to 5 degrees and a -30 to +30-degree swing angle bit it is more than this). This should make it good for use on moving targets or uneven ground. Even with the spring it is still really steady on full extension looking at objects 300m away.
On the downside it takes a touch longer to deploy but it's only a 1/3 twist to loosen and tighten each leg (there are 2 extensions).
The attachment to the sling stud is a bit tricky if you are just using your fingers... using a small screw driver its fine.
If your sling stud was to far forward it might hang off the end too far.It just hangs off the front of the Lithgow stock.
If you had a Schnabel forearm on your rifle it may not fit real well unless you shift the sling stud back.
When retracted the legs still stick out past the end of the barrel, they probably wont on the Tikka.
Even with those minor issues I'd highly recommended a Vanguard Equalizer 2
Shown below with 1 section extended (approx 20 inches)
https://www.youtube.com/watch?v=dUY78_LFcV8 review by some South African