Hi, I’m looking for my 1st full sus bike and can currently get a Scott Genius 710 2018 for a very good price. However it has Shimano XT CS-M8000 / 11-42 T and wondered what I would need to convert to Sram Eagle 10-50?
Or should I just buy a 2019 Genius 930 for similar money?

2×11 on that bike. If you buy it, I’d see how you get on with the XT first and maybe consider it further down the line?

You’d need to either get the NX boat anchor cassette, or another 12 speed HG freehub one, or change the freehub to an XD for the nicer Sram cassettes. Then buy a shifter, rear mech and chain (plus a n/w front ring).

It would be a bit of a bodgy upgrade as described above. You might be better off going 1×10 with a smaller chainring for now and either waiting to see whether Syncros brings out a retrofit version of the microspline hub, or, if you plan to upgrade the wheelset, giving yourself a choice of Eagle or new Shimano 12 speed at that point.

My bike came with the 2×11 XT (40t rear). I am happy with it and when it wears out i am going to 1×11 and throw a 42t on the back and get a 30 or 32t for the front. Much cheaper than going 12speed from the off.

Sunrace 11-50 cassette will get you almost eagle range and will be far cheaper if you just want to go 1 x 11.

Just stick with the 2x until it wears out and then see what’s available. 1x isn’t really an upgrade.

That’s my plan with my Jeffsy.

The only downside to 2x is not being able to run an underbar dropper lever.

1x is nicer than 2x in my experience.

Advantages

Drops the chain less
Don’t need to worry about front shifting
Can run an under bar dropper lever

Disadvantages

You can lose range – although 10-50 cassettes make most of it back

Heavier cassette (depending on the one you get)

I haven’t looked at the bike you mention but if it’s 2×11 I’m assuming the rear mech can handle a bigger cassette – say the shimano 11-46. If so you don’t need to change your freewheel body and all you’ll need to do is buy the cassette / sort out a narrow wide ring for the cranks – assuming you can get an ok chainline with the 2x crank.

To go eagle or shimano 12 speed you’ll need a different freehub body, a different mech, a different shifter, and a different cassette. Again you then need to think about a chainring for the front. Eagle chainrings are better than normal narrow wide ones from what I’ve seen but you might not get one to fit your existing crank.

If the model you’re looking at has better suspension than the 2019 one is probably get it and just try a bigger cassette and losing 1 front chainring for a narrow/wide one. As mentioned above, if the standard rear mech will stretch to it, Suntour do that mentioned 11-50.