SHMUPmame: Yay or Nay?

[kiteJargon]

Has anyone tried this variation of MAME? I found it on the shmupsforum the other day and supposedly it takes 1 or 2 frames of input lag out of various MAME shmups. The only issue is that it's now using the MAME99 core which is a pain in the ass as I've updated all my MAME roms to latest and many of them do not work in the older version.
My question is basically, is it worth the effort to find the older versions of all of these roms? To be honest I didn't notice a difference when I tried out Batsugan.
Do any of you notice the speedup in response time?
Experienced 'shmup'ers please chime in!
Thanks in advance.

[Hatta]

I use it, but I don't really notice much difference. I'd rather be sure that I'm using the lowest latency setup possible, than wonder if I'd do better with less lag.

Now that I think about it, I haven't updated since the first release which built against mainline MAME. I guess they're building against MAMEPLUS! 99 now? That's kind of a shame. Instead of forking MAME, they should really be trying to get their patches into mainline MAME. I looked around for a bit, and I can't even find the source to MAMEPLUS! 99.

[Bradtemple87]

I had not heard of this one before, very cool

[Shogun]

I use 2.2 and theres quite a difference. Plus it eliminates lag on many other games so it'd be good for fighters for example. 3.0b is based on Mame v .99 so many of my roms are broken. Some people prefer to use that version but I'm fine with 2.2. Definitely recommended. Once I started using it I never looked back.

[Itchyant]

I use 2.2, haven't noticed the lag difference much but I was able to download a complete package that included the roms so I didn't have to go searching or updating.

One minor gripe is that I can't get save states working on DDP, but other than that its pretty cool.