One thing you may notice is that the charging handle is very tough to pull. It's not the strength of actually pulling it; it's the wear on your pulling finger as it digs in. I got the extension for it and it really makes the difference.
I can't comment on the out of the box performance as mine came with a damaged cylinder head so by the time I first skirmished it properly, it had a new spring, barrel, cylinder head, piston, trigger sears and hop unit! It's also a BIG gun. Mines huge....so to speak. I've got a suppressor on mine and when stood with the stock on the floor, it comes up to my chin!
What I would recommend though, are optic rails from Kalinka Optics if you are not going for the POSP-1 scope.
I use this:
http://kalinkaoptics.com/mounts/svd-psl-tigr-romak-3/original-bp-02-svd-psl-tigr-low-profile-centered-side-mount-to-weaver-rail.html
The universal mount that a lot of people put on is too high, so some scopes won't zero in properly as they won't look low enough. It can also give a strange visual effect from parallax which makes it look like the bb is bending into it's target when it is in fact going perfectly straight.
Before suppressor mod:
After, next to my SCAR and UMP.
http://www.airsoft-forums.co.uk/index.php/topic/3820-gun-picture-thread/page-110#entry143368 (cant find the original picture).
One good thing; it takes AEG parts. It is very easy to install parts.
I would recommend the spring SVD. It certainly turns heads...and with the suppressor on it is so quiet.
List of upgrades: AirsoftPro.cz Upgraded trigger sears
AirsoftPro.cz Upgraded hop unit
AirsoftPro.cz Upgraded outer/inner barrel holding unit
M140 spring
AirsoftPro.cz Reinforced piston
AirsoftPro.cz Reinforced cylinder head
Madbull 6.03 650mm tightbore barrel
Forgotten brand red hop rubber
AirsoftPro Suppressor adapter (nicely cushions the end of the tight bore barrel)
Kalinka optic mount
Black handguard/grip furniture (previously 2-tone)
AirsoftPro.cz Charging handle extension
Soon to be getting a prometheus hop rubber as my other hard rubber shredded during a strip down :/