I'll preface this all by saying that my favourite bolt action platform is the Tanaka m700 system. While Tanaka may be incredibly hard to get now, KJW m700s are easier, but still not easy, to find and they're phenomenal rifles (I literally have 2, plus a Tanaka and they're my go-to bolt actions). However, I wouldn't advise buying one if you're just looking to get into sniping because they're incredibly fussy and require a lot of patience, since every game day you have to tweak them to make sure the power is where you want it, since temperature will affect power due to being powered by green gas. You can HPA them, but in my opinion it's impractical as you have to HPA tap the mags, meaning every time you reload you have to detach and reattach the hose, where a HPA VSR you don't have to do that.
With that said... In my opinion, the VSR platform is still king due to just how much stuff is out there for it. Some people love the SRS (I don't!), and apparently the Steyr Scout and the Tac41 are pretty decent, but the VSR10 platform still reigns supreme in my opinion due to the sheer amount of aftermarket parts. I also think it depends how much you're willing to get into the thick of it and how much you value certain things. Generally, buying an expensive TM VSR over a JG BAR10 or Cyma cm.701b isn't worth it as you're basically removing all the internals anyway, so why spend that extra £70 on a TM?
Having done multiple VSR builds, I would personally always go for the TM, even if I'm replacing everything inside. Part of it is that I think the G-Spec is the superior option over the regular rifle, and I don't think you can get a clone G-Spec rifle. The other part of it is the tiny fraction of a millimetre tolerances and slight quality of life differences. Firstly, the sling mounts on the JG are awful and I've had to loctite mine in. Secondly, not everything will fit perfectly in a clone rifle. I found that the 50rd Action Army magazines are very fussy with my JG BAR10 and I've found myself just running the regular 35rd TM magazines as the Action Army mags would sometimes have feeding issues, or they wouldn't click into place properly. That said, for 99% of people the clone ones are absolutely fine. I'm just very picky!
Also, when it comes to "sniping",
@Tackle is completely right in saying that fieldcraft and mindset is more important than your rifle. I've played the sniper role with (a lot of) bolt actions, DMRs and regular rifles, and very little changes in how I play. It's more about the stealth and picking your shots than having a 2.3J bolt action with an MED. Also, if you go the whole way into it, it's honestly more about observation than shooting; one of the best sniper games I've had involved me not firing a single shot all game, but I was concealed and constantly calling out enemy movements over the radio to some other guys on my team, so we always knew what the other team was doing. Even had a patrol of about 8 of them walk right in front of me and one crouched down about 50cm to my right. When it comes to actually shooting, the words of some German guys I used to play airsoft with in Spain will always resonate with me as I feel they encapsulated airsoft sniping so well in one simple sentence: "it's not how many you hit, but how you hit them."
You'll never (well, incredibly rarely to the point where it's a statistical anomaly) get as many hits in game using a bolt action rifle as you would with a regular AEG, but every hit you do get will feel so much better!
