I used to love the Machina... because I still want the Sniper to get some kind of real Railgun weapon. The Machina is close, especially with the penetration shot, but let's face it, it doesn't happen often enough to be a big plus compared to not being able to noscope.
The regular Sniper Rifle is still one of the best snipers obviously. I really like the Heatmaker, as it forces you to aim for the head (compared to bodyshot-machina). I've been trying to use the Baazar lately... and sometimes it's great and I can keep enough heads... but sometimes I'm terrible and can't even keep 1-2 heads.
I never really noticed that Machina tracer lag though.